I thought I read somewhere, possibly on here, that someone flipped the radiator's mounting and got it to vent upward out of the vents in their GT3 nose. No idea how easy/difficult/effective it is, but that may be a possibility for anyone that does go or has gone the GT3 route.

kpaz did it on his subi build, but he also removed his front bumper to give the air someplace to go, as well as some fabrication to make it work (the rad bracket and the rubber gasket that joints rad to bumper cover).

The Boxzilla project had a functional top vent for the center rad that reminded me of a Ford GT40, might be some good ideas there.

I've got my car modded for the center radiator inlet to vent over the hood instead of under the car. The bumper is a 996 GT3 replica, but I had done the same thing with my stock 986 cover. Moving the radiator isn't too difficult, but you do need to lengthen the hoses. On the 986 cover, I used some sheet metal behind the radiator to direct flow to the vents and over the top. On the GT3 cover, there are no holes underneath, so air has nowhere to go but through the vents in the nose.
On the highway at 70-80, the car is very stable. I've hit 100 or so during an AX (on a NASCAR track) and didn't notice and lightness to the front end. Haven't been to VIR for some real speed yet, but hopefully in the spring!

One big advantage I noticed is that the temps drop faster when you go from "in town stop and go" to highway cruising speeds.

I don't have much experience driving the car at very high speeds. That said, the little bit I did drive at high speeds I felt the back end get light. I didn't notice the front getting light. What have others experienced in this area? I'm a little surprised there's so much talk about the front getting light.

Try sliding along the pavement upside down. It brings a whole new appreciation of steel.

He may have been referring specifically to the Boxster's hardtop.

I thought I read in a book from Porsche that the top speed for the 2000S is 157 and the aero kit adds another 15 mph.
Ken

Unstable at 129? That seems pretty low to feel unstable. I've had mine at 135 and it felt fine, same as 60

Recently I had my stock 2.5 at 135-140mph according to speedo (which gps says is about 7% over reality) and I changed lanes on a closed course and didn't notice lightness. Only other car I've had that fast was a LT1 Caprice police car and it felt VERY light at 130 despite the car weighing 4300 lbs

Aero kits usually lower top speed, in this particular instance there is no way it will add 15mph.

+1
Every car I ever saw with a "full aero kit" was 15mph slower. YMMV

RE the OP: 135mph indicated in turn 1 at Auto Club Speedway. GPS data logger says 130.

How fast were you driving last night in the St. Louis area when you hit that poor young lady with your Porsche Boxster?

That, of course, depends on the speed you are doing. Mine is off 3 mph based on many GPS comparisons. At 50 mph - that's 6%, but at 100 mph it's only 3%. Since I'm generally between 80 & 85 mph on the highway, mine is therefore off .03529%. Certainly not enough to worry about.