8 to 5 lug

[jr2k3_esq]

Hey guys,
forgive me if this is in the wrong spot, but I need some direction. I know it's been asked lots but just correct me as I go along.

I have a 1970 LWB C20 (the hand painted blue one I got for $400), and am just going to start a 5 lug swap onto it. I have a parts truck givin to me that is the 73-87 body style, but there is no cab on it so I don't know what year it is. From what I have been reading on here if I unbolt the front cross member from the parts truck, I should be able to bolt everything spindle to spindle into my C20 (drilling 2 more holes for a total of 14 holding the cross member in) correct?

Is it a better way to go swapping cross members? or just bolting everything to the 3/4 ton cross member? If I swap cross members will I need to pull my engine? or just lift it enough to sneak in there. The parts truck is now down to a rolling chassis so everything is accessable, and the C20 I took the fenders, hood, cowl, grille, and bumper off tonight.

If I replace parts on the front end I will need to use parts from whatever year the parts truck is, but are all the part numbers the same from 73-87?

When I go to bolt the leaf 5 lug rear into my leaf rear of the C20 will the spring hangers match up? This is my first time diving into something like a "project" and I am a noob when it comes to welding and fabbing. The truck used to be parked at a buddys 45 minutes away so I never had the ambition to work on it and get something started, now it's 3 minutes away at my brother in laws and I am stoked. Thanks for your time, any tips, info, help, pointers is muchly appreciated, just ask if you need more info from me and I can get back to you.

-JR

[basemodel67]

I would think it would be best to pull the motor since the mounts mount to the crossmember you are replacing. But that's just me- I don't like death by falling engine.