The breather for both my 89 and 90 TGP, from the factory, were routed straight into the air intake box.
I took off that system when I installed my directed warm air intake, and just put a breather on. I wish I had done a catch can instead.
Mine did not have a PCV system. When I had the intake manifold off, there was a plug/cap on the port where the PCV would have plugged in. There was nothing in my rear valve cover.