Wouldnt i need new wiring for it and wouldnt the wiring on a extended cab or regular cab be too short

 

For the engine/trans, I don't think it matters. They mount in the same place, all the sensors would be in the same place. It will require some re-pinning though, to incorporate it with the interior harness...... Not sure just how much though.

 

The sensors are not in the same place. Not even close.

As I stated previously...the 3.7/4.7/5.7 engines are completely different from the 3.9/5.2/5.9 engines. The sensor locations are different, the PCM is different, the wiring harness is different, the radiator shroud is different, the ABS configuration is different (pushrod = RWAL standard, 4WAL option; OHC = RWAL base model only), the cluster is different, the transmission is COMLPETELY different, the crossmember is different, driveshaft is different. I may have forgotten a few things.

Chassis length does not matter, the body/chassis connector is located in the driver front fenderwell.

To properly convert a truck from NexGen to pushrod or pushrod to NexGen, you're basically doing a chassis/body swap, but then moving over several components from the old body/chassis.

It's not worth the time.

 

I agree with Magnethead on this. It's not worth the time.

He's correct that the engines, PCM, harnesses, etc. are completely different. You'll run into all sorts of mechanical and electrical challenges in getting it to work.

A replacement 3.7 would end up being far cheaper in the long run.