I pretty stock R33 in good condition, should be able to run around the track all day long even in 33 degree heat with the stock radiator. There is a problem there, that I would be tending too first.
Other than that you have got the rite idea. FMIC, Oil cooler, air guides for RAD, good quality coolant, & PowerFC or just as good, with a Good safe tune.. etc etc would be my first choices too.
good luck with that. keep in mind, you also might want to consider decent quality oils for, engine, diff, gearbox, brakes. if your going to track it.