CPP tubular engine & trans crossmembers

[G&R's57GMC]

Hang your engine and trans on your hoist,

hover it in the engine bay,

mount the cross members to the engine and trans,

find the best location,

Level Side to side and front to rear using the manifold carb mounting surface,

bolt to chassis, Tack weld the cross members to the end parts,

remove engine,

finish weld the pieces .

E Z Pee Zee

This assumes the cab is in place. Don't be surprised if the trans mount is below the frame rail.
BTW the driveshaft will need to clear the next factory cross member through in its range of motion.