The T5 is a bit light for a 3/4 ton truck.
There is no need to fabricate a crossmember. You will likely have to remove the carrier bearing crossmember that is behind the sm420. You will also need a new driveshaft made. A 1 piece driveshaft should be fine, but you might need to make it 4 inches diameter.
Find the e brake setup from a 1/2 ton. The pistol grip dash lever will be easier to adapt. You will also need the pulley, rod, and swivel bracket.
