My TR-4 is going to the track!

Guys -
I've got a '62 TR-4 that I'm going to do a little work on this winter, in preparation for some track time when the snows melt.
(I'm in the mountains west of Denver; the nearest track is High Plains Speedway, over towards Kansas; and the car is a VERY faithful friend that I picked up in Belgium for $550 maybe 30 years ago.)

I've got no road-course experience (this venture was triggered by an unusual article in Hot Rod magazine!), and I'd welcome any advice you guys can offer.

My initial planning calls for: 1) replacing all the Triumph's bodily fluids (the Hot Rod article suggested eschewing anti-freeze, to help keep the track clean); 2) removing stuff like bumpers, spare tire, etc. that I don't really need anyway; 3) installing a roll bar; and 4) re-doing the brakes. (This last step is motivated by my sense, whenever I'm driving the little guy, that my top speed is limited by my awareness that sooner or later I'm gonna have to find a way to get stopped again.)

(About the braking: Does anybody make the parts to convert the rear drums to discs? Does this help as much as it ought to? Is such a conversion legal, vis-à-vis the rules of the various vintage-racing organizations? Or should I just grind the rotors and drums, install new hoses and pads, and leave it at that?)

Any help or advice would be greatly appreciated, guys. (Except for: Are you out of your mind? My wife's already offered that.)
Neil