Magnum 360 rebuild help

If you're on a budget, just check out the rod bearings, main bearings 1-4, and if all looks good you are probably in business. Used factory lifters are more reliable than anything you can buy new and they even work with bigger camshafts. Just make sure the roller wheels spin smoothly by hand while they are out.
Factory rocker arms can stay if in good shape. Check for scuffing in the pushrod cups though.
Pretty much everyone will agree the stock factory and replacement springs are not good enough, unless you keep the rpm very low. Install the Hughes spring and retainer kit even if keeping the stock camshaft.
With the 7 1/4 rear end, you decide. I broke one in a body with stock 318 and lots of burnouts. Also had one last the life of Diplomat behind a slant six.