Hey y'all; thought I'd post up pics and a description of my new PCV system. I've gone the familiar "vent the valve covers" route, but unlike most/all of the other approaches I've seen, I ended up NOT welding in fittings. Instead, I used two Swagelok SS-810-71-8 Bulkhead Female Connectors, which are threaded for 1/2 NPT fittings. I drilled a 3/4" hole in each valve cover, centered 1/2" below the groove/rib that runs along the tops of the covers. This left just enough room to install the nuts on the male-threaded part of the fitting. I took a peek through the oil fill hole, and there's also generous clearance between the fittings and the head studs and other protruding bits underneath the valve covers. Each of the fittings also has two o-rings, one on the outside and one on the inside, and I used blue threadlocker to help hold the nuts in place.
Here's what it looks like:
On the outside, I used 1/2" NPT x 5/8" i.d. hose barbs, as well as 5/8" i.d. heater hose elbows and tees, to vent the valve covers to the catch can:
The catch can is mounted to a bracket which bolts to the top of the intake, where the coil pack used to sit (I'm using a Neon coil pack that's mounted on top of the valve covers). On the bottom there's a small stop---- (EDIT: stopcawk), meant for a radiator, being used as a drain fitting:
I have also plumbed in a 5/8" line from the vent galley on the block, and a 1/2" line leading to a TT Supra PCV valve, which is then stepped down to a 3/8" line that leads to the intake (there's also a smaller bit of line in between the valve and the 3/8" piece; I think it's maybe 5/16"):
Overall, I'm very happy with how it turned out. It's not as pretty an install as some, especially with the big clunky fittings on the outside of the valve covers and all the heater hose running everywhere, but works well and was surprisingly easy to set up.
I do have a few concerns:
(1) Need to replace the dirty old filter that came with the catch can; looking for something with about a 42mm opening.
(2) I need to trim about 1/2" off of the upper radiator hose at the thermostat housing so that all of the tubes can co-exist nicely.
(3) I'm a bit worried about putting the catch can in the path of the fan; hopefully it's not going to make much of a dent in how much air's getting pulled through the radiator.
(4) The valve cover fittings are not baffled, so I might end up blowing a bunch of oil down to the can. I'm hoping that the slight downward angle of the fitting (because of the just-barely-sloping sides of the valve covers) will cause most oil to just drip back down. We'll see.
(4) I'm not really sure whether it's wise to run a line from the catch can to the intake manifold: even though I've stuffed the can full of steel scrubbing pads, I don't particularly like the idea of a bunch of air going through the catch can's filter while the engine's under vacuum. On the other hand, when I bought the car, it had a cone intake filter and most of the original intake setup was gone; the part of the PCV system that used to be connected to the stock air filter housing was just venting to atmosphere. So at least the new system is a step up from that. Also, I'm still pulling 17-18 inches hg at idle, and the A/F ratio is dead on.
I would love to get questions, comments, or criticism. Thanks!
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12.57@104 :O) 
