i don't know about a 5.3 but i am puting a 92 tbi motor in my 72 c10, the question is are you just using the engine or are you doing the full swap with fuel injection, electronic transmission, engine management and all. If you are just using the engine alone , i believe that summitt sells the intake, dist, and exhaust manifolds to make this engine carburated. either way i know early classic sells the motor mount kit for this swap.I also know that the folks at year one did a full swap in a 69 camaro and they even sell some of the conversion goodies as well. hope this helps and good luck, don't be afraid to try this, i know it can be done