>>In fact, these mods that I'm proposing are partially prompted because I hope to do some SOLO this summer, and also get on track with a friend of mine who's a Land Rover mechanic, part-time ALMS driver, and Triumph Spitfire Le Mans, Diasio, and seriously track prepared MCS driver.
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That's a good idea, nothing like seat time on an autox course to teach you what you don't know.

Actually, if you're really serious about participating in competition, and want to be able to measure your progress against other competitive drivers, you may want to hold off on any mods (other than a set of racing wheels and tires) until you scope this out a bit. Intake or pulley will knock you out of SCCA Solo II Stock classes, and into super competitive STX or other classes that take a lot more money to play in. A cat back exhaust is okay for stock, but might not be the best bang for the buck.

So, if you are a rational driver on the street, you may not need any mods all all, particularly if you don't want to get into a wallet race on the course.

I'm running in G Stock this year, when I start into STX I'm going to be jumping off a money cliff. LSD will be first, all the rest won't do me much good until I have one of those!

Good luck!