I've had a very limited experience with the M-2 suspension, and what I've had has not been good. It gives the truck a nasty-looking droop snoot, with the front bumper almost dragging the ground. Some people like that, I guess, but there's just no way to achieve a level ride attitude, because of the way the system attaches to the frame. Lowering, within reason, doesn't pazrticularly bother me, but I feel the truck should have approximately the same bumper height front and rear, and the caster angle should allow for normal steering wheel return toward center after a turn. Also, the M-2 system was engineered for a 4-cylinder compact car, not a 4,000-lb. truck with a V-8 engine right over the front suspension. It's sending a boy to do a man's job, especially when it's combined with a rack & pinion steering system.
My 54 pickup is getting a re-frame job, with a mid-70's Nova frame and suspension grafted onto a mid-80's S-10 leaf spring rear frame. That puts the body and bed onto a disc-brake independent front end, with all the engine mounts, steering, and suspension already in place from a V-8 powered modern vehicle. No guesswork engineering, and if I want an altered ride height, there are plenty of custom-height springs available through NASCAR suppliers, in all sorts of weight-bearing capacities.
The 59 Burb is getting a narrowed mid-80's disc brake 3/4 ton suspension, to match the lug bolt pattern from the Dana 60 positraction rear axle out of a late-70's GMC. It's going to be powered by a Caddy 500 engine, and a Turbo 400 trans. It's going to be my trailer towing rig. That one's a bit more tricky, because the crossmember, and the relay rod has to be narrowed, plus I'll have to fabricate mounts for the steering gear and the idler arm. The standard-width 3/4 ton crossmember is a bit too wide for the 59 frame without some modification.
Whatever your choice for powertrain and suspension, please make safety and reliability your top priority, and take advantage of as much factory-type engineering as possible. Too many hot rodders end up going for appearance ahead of safety, sometimes because they just don't know any better, or they believe the advice of someone who is going to solve all their problems by selling them something. I'm not a salesman! Drop by the school shop sometime, and let's talk!
Jerry
