03 silverado 4.3 to 5.3

[jsisk]

You can use any 01+ engine. The only difference in the actual engine between pre-03 and post-03 is the throttle body. And returnless or return fuel rails. Easy to swap either around.

Thanks Frenchy,how do i know if i have a return fuel set up?I have to lines that run into my spider injection but i seen on here it might be returnless.

[Frenchy]

Your trucks an 03? It's a return setup

[jsisk]

Your trucks an 03? It's a return setup

Thanks again lol ill stop being a pest now and get to work got my engine mounts in from dealer and new clutch kit and fly wheels