Great call, BlueBlast! We had a couple of brothers showed up in a new 997 S a few yrs ago and one of them showed some real skills. After a season on the track a couple of us suggested they get a Miata to learn how to drive a momenteum car, one that wouldn't mask their mistakes with heavy doses of hp, and holy bat droppings, they did! And now they're faster in the Miata than they were in the C2....and racing the Miata very successfully. As I write this we just finished up a 3 day
PCA event at LCMT (Le Circuit Mt Tremblant) and a top Miata and P/Car pilot spanked a very significant percentage of the field in his Miata.
My only suggestion would be to buy one that's already built...take it from someone whose been down that slippery slope too many times. Let the other poor sucker take the 40-50% hit on the conversion from street to track!
Have fun!