I would only add that I don't think it is probably necessary.
I know guys who have killed a 901 or two behind their V8, and I know several more who have 901's living quite nicely behind their V8's (including me). I think the important thing is that those who have killed their 901s did so with behavior that no trans cooler in the world would have affected, i.e. shock loading. Dump the clutch too often, break the trans. It's that simple. A cooler won't do a fuching thing to prevent that.
My trans is 4 years old, the PO admitted to me he dumped the clutch more often than he should have, and I do it once in a while, but I get on hard it often. I put 1500-2000 miles a month on the car in season, and the trans now has 20,000 miles on it. When Brad Meyeur opened my trans in January to do the gear flip/swap, it was all so clean and new inside, he only replaced parts that had to be switched to accomplish the swap. All other parts were perfect, and went right back in. In fact, if anything, I wish my 2nd gear synchro (now 1st gear in an 8) would wear a bit more so it would slide into gear at a stop a little easier.
Now, if you are gonna race it, that is a whole different ani-mule, in which case, neeevermind what I just said.