My current 48 is sitting on a complete (though shortened 8") Dakota frame (standard cab, long box, 124" wheel base). The rear of Dakota frame kicks up pretty high at the rear axle and remains high to the end of the frame, if you use the whole frame, major modification will be required to the floor pan from the axle kick up to the rear bumper.

At one time I started putting a Dakota front frame on a 39 Plymouth (same basic frame as the 46-48 except it still had the X trans crossmember) and the Dakota frame slid inside the original frame at the firewall.

A Dakota frame has straight boxed frame rails from the kick out behind the front suspension until it kicks up for the rear axle (in the 5' long straight stretch range). They came with rack & pinion steering, independent, modern suspension (all new design in 87), disc brakes, have a lowering kit available, and support a 4 cylinder to a V8 with simple coil spring change. The track width of a 1st gen Dakota is about 60", about the same as many older Mopar cars & trucks. The 87-90 had 5 bolt 4 1/2" bolt pattern, the 91-96 have a 6 bolt wheel but can be converted to 5 bolt by bolting on the older rotors and changing rear axle shafts from the same size rear axle. The 97 & newer would be better to keep the 6 bolt wheels. You will want to look over the early Dakota frames for rust about the center of the truck about the point of the factory splice between the boxed frame and the channel back portion, especially rust belt trucks. Its not a difficult fix, and its usually the bottom 2", but its something to consider if you have a choice of more then 1 frame.

If I was going to clip one, the Dakota would be my 1st choice. Gene