Here's what I did for my chevelle:
Take absolutely every nut and bolt off it.
Check for straightness.
Grind and MIG weld over all the factory welds (which look like chicken poop)
Box it for stiffness if it's not already, gusset anything that looks weak.
Check for straightness (all that welding might cause warpage)
Mock up engine/trans, narrow crossmember, make crossmember brackets.
Sandblast, prime, and paint.
Too bad i ran out of money, and that's as far as I got
