Well I did the swap yesterday afternoon. I swapped the upper intake manifold(plenum) only, the lowers were the same. Wasnt too bad of a job, tight space to work but pretty straight foward. Only problem was every little plastic vac line broke off, but I had some small rubber line to fix them with. Did a plug change while I had the plenum off..easiest one ever, just reach straight across, no contortions.
The end result was well worth it, the van is like a new vechile, it just goes! Runs strong and no more lag while carrying a load, even up hills..had to go get 6 bags of mortar mix at 80 lbs each. Still fine tuning the idle etc, but Im very pleased with the end result. I feel like I have a sport van now!