You can do anything you want to the intake manifold so long as you preserve the original function - you have it face the ground 180 degrees backwards so long as the EGR/PCV are still present. You don't even have to run a stock one. "Intake manifold modifications" are explicitly legal as long as original function is maintained.
I put a 1985 manifold on a 1994 engine in my Saab and had no issues getting it approved. Zero hassle, explicitly exempt.
BOVs are not legal since they result in false air readings, but BPVs are 100% legal. I have an Audi 710N ("Bosch style") BPV on the XR and have for years. 100% legal.
We've all had this discussion before. Search "Appendix G" on the forum. I've posted it easily a half dozen times.