heres how mine ended up after i installed my dual cases.
that crossmember is from
www.budbuilt.com its designed to mount in the stock location (which you can see on the left side of that picture) or you can slide it back on the frame and bolt it up with stock rear toyota u bolts that you probably have laying around.
that piece of rubber inbetween the frame and crossmember is to try and absorb some vibrations. my only problem with my dual cases is that i bought the marlin crawler rotated dual case adapter, so the rear transfercase is rotated 10 degrees, making it impossible to use the factory rubber transfercase mount. i made a steel mount for the rotated tcase and welded it to the crossmember. its super solid and eliminated ALL of my drivetrain movement, but it makes the truck vibrate a lot. the cab resonates all the vibrations and makes my truck a real noisy ride.
oh and get dual cases rather than 4.7s. you will LOVE having all the gear options of 2 transfercases, its like, the best.
sweet truck by the way, frankenyotas have so much character