Hopefully other members will provide their opinions so you're not just listening to my input, but unless you’re an experienced fabricator, I’d suggest the most useful Monte Carlo components are:
• Engine with all accessories
• Transmission if it’s a type you want
• Driveshaft (which may need modification)
• Intermediate steering shaft (between the bottom of the steering column and the steering box – should you choose to upgrade to power steering you may be able to use this part).
• All the light bulbs and electrical components including the brake light switch.
• The steering column is a matter of choice. If it’s clunky and ugly you may not want it in your classic truck, although many do use these newer style columns.
Theoretically you can also use the entire wiring harness out of the car. I did this long ago transferring every piece of wiring and bulb socket from a Nova to a 46 Ford. In the end I was sorry I wasted so much effort. I spent as much money buying spools of inferior wire at the parts store to splice it all together as it would have cost for a decent aftermarket kit, so I don’t recommend it.
Unless there is something wrong with your rear axle, if the truck turns out to have a Dana I would rather keep that than swap to something else. The Monte rear axle could be used if the wheel mounting surface to mounting surface is close to the original truck width. If it’s narrower this could be compensated by custom wheel offset, and might allow for deeper wheels. Swapping axles will require stripping all the brackets and welding on new perches. I think CPP or Early Classics may sell the correct perches with the angles engineered in. You need to find someone that knows what they’re doing to weld on the new mounts so the housing does not warp causing bearing problems in the future.
A front suspension swap to a 73-87 would be far easier than trying to use the Monte Carlo. Again, if you’re an experienced fabricator, the truck could be sub-framed by cutting off the front of the Monte at the firewall, and welding it to the front of the truck frame. This is effective, particularly if you want to substantially lower the truck. But I’ve also seen many street rods ruined when this wasn’t done correctly. You’d need to do a lot of measuring to see if the two frames are close enough dimensionally to make this practical. For me, I would rather do something I can bolt together than trust the results of cutting my frame in half.
