my buddy has a 99 4.3 and needs a motor, but my other friend has a 04 4.3 that was going in an offroad beetle but decided to go with a LS motor instead. I understand the 04 doesnt have an egr and has a different injection system, but what I want to know is if you swap the intake and exhaust manifolds is that all you need to do or is there more involved im missing?

 

Keep the injection setup from the '04, but swap the lower intake manifold over. Also, you will have to drill & tap the hole in the back of the block for the knock sensor. The '04 KS bolts on while the '99 threads into a 1/4" NPT hole.