Seats front and rear are virtually bolster free and borderline over-stuffed, much like what might be found in the den of an upscale house or in an airline first-class cabin. An oversize center console with a deep storage bin separates the two front seats, which are adjustable along multiple planes. The rear seat, which is rather upright and fixed, can sit three, but with a fold-down center armrest, it's more inviting for two.

Against the most sensible competition, the Cadillac Escalade EXT, there's little difference in dimensions. Headroom front and rear varies by less than an inch, likewise legroom, which is ample. Hip room is more problematical, as the way it's measured can mislead. The Mark LT's front seat width is listed at almost 64 inches, but this is side to side between the inside door trim and without accounting for the center console, which is far from slender. The EXT's front-seat hip room is listed at 62 inches, but this also includes a substantial center console. Our memory tells us the Mark LT's front seats are the roomier, but this reflects as well our comfort with the busy-ness of the inside door panels, the shape of the seat cushions, etc. Best to try, then decide. We're more comfortable assessing the rear seat. The Mark LT's back seats promise 63.1 inches of hip room, the EXT's 62 inches. In that the design and style of the seats are similar, essentially benches with split, fold-down backs, the Mark LT's extra inch-plus directly translates into more hip room. The Mark LT's rear door openings are more welcoming, too, than the EXT's, which offer less clearance between the seats and door edges at floor level, to the point we had to turn our feet sideways when climbing in and out of the Cadillac's back seat. The EXT comes out ahead on one major interior measure: Front-seat side impact airbags are standard, which are not available on the Mark LT.

The way the Lincoln Mark LT's interior interfaces with occupants is virtually all positive, even more so when compared with the Cadillac EXT's chunky, cheap-feeling, outdated, over-done, ad hoc hodgepodge of panels and switches. In contrast, the Mark LT's dash is smooth and sleek, with sharply defined, vertical panels and well-spaced, supremely functional ventilation registers. The instrument cluster is a quiet, symmetrical assemblage of well-shaded, round, easily scanned analog gauges. The speedometer dominates, with a slightly smaller tachometer to the left and a combination voltage and oil pressure twin to the right; the last houses the information display with compass heading, ambient temperature, odo/trip meter and vehicle system warnings. Tucked into the saddles between the two side gauges and the center speedometer are needles reporting fuel level and coolant temperature. Large buttons managing the essential cruise control, audio and air conditioning settings bracket the sizable steering wheel hub.

The stereo control head occupies the top third of the center stack, with the air conditioning controls directly below. The bottom third is filled with a cigarette lighter and the reverse parking sensor on/off switch above an iconic Lincoln label. All controls are intuitively marked, finger-friendly and ergonomically arrayed. The only disappointment is the lack of a proper tuning knob for the stereo; in lieu, there's either scanning or seeking, both agonizingly slow processes. Give the Cadillac EXT credit, though, for a feature not offered on the '06 Mark LT: a navigation system.

A surprisingly comfortable, ice cream scoop handle-like gear lever stands proud out of a chromed shift gate in an equally sleek and uncluttered center console. Next door, on the passenger side, is a pair of cup holders with removable inserts to accommodate oversized soft drink cups. Just aft is the padded cover on the center console, behind which are two more cup holders serving rear seat passengers. The backside of the console houses a power point and, when so optioned, auxiliary jacks for the entertainment system.

There's a choice of overhead arrangements: a longitudinal assembly of flip-down storage bins and, when ordered, screen and control head for the entertainment system all suspended from Ford's F-Series' powered rail system, or a power moonroof. Included with the entertainment system, and available as a stand-alone option, is Sirius Satellite Radio. Cadillac, however, includes XM Satellite Radio on the EXT at no extra charge. As for other storage on the LT, there's the glove box, of course, plus map pockets in doors and magazine pouches on the backsides of the front seatbacks, with space for occasional storage beneath the flip-up rear seat.

The Mark LT is a pickup, remember, which means there's a bed out back. Given the crew cab configuration, it's a moderately truncated box, a mere 5.5 feet in length. Lincoln offers an extender, a tubular construction that pivots up out of the bed to rest on the open tailgate, effectively lengthening the bed by about a foot and a half for some cargoes. When not extended, and with the tailgate up, the bed extender provides a confined storage area we found helpful for holding grocery bags, gardening gear and plants for weekend yard projects and the like. There is a downside to this setup, though. Because it creates two, smallish compartments of roughly the same size, the bed extender also renders the bed for the most part unusable for anything else. It's designed for easy removal and reinstallation, but you'll have to store it when it's not installed.

The Cadillac EXT counters with its mid-gate system, comprising a removable rear bulkhead and window. With the mid-gate out, the EXT's bed extends into the rear seat area, effectively stretching usable length from 5.25 feet to eight feet. There is a downside to the mid-gate, too, however. The tracks in which the mid-gate seats are known to collect dirt and other stubborn detritus over time that interfere with the mid-gate sealing properly. Plus, of course, you lose the back seats when the mid-gate is lowered.

On balance, we'll take the Mark LT's bed extender. We would, however, not opt for the chrome box rails. The LT's box sides, like those of the F-150, are already abnormally high, and adding the rails makes the bed even less accessible from the sides.

We also appreciated very much the Mark LT's Tailgate Assist, an internal torsion bar linked to the tailgate's hinge that bears some of the tailgate's weight, lightening the load when opening and closing it. And then there's the delicious irony of a tailgate that's both lockable to deter theft and fitted with hinges designed for easy removal.