PS: OEM
Coolant: OEM
Brake fluid: Motul RBF600
Clutch: OEM or whatever I have lying around
Gearbox: OEM MTF or Red Line MTL
Engine oil: Red Line 10W-30 or 10W-40

This is in a DC5R, plenty of track work. I've probably done 2000-2500 track km in this car, 138,000 km overall. I change engine oil and brake fluid every 2 track days, gearbox oil every track day and the other stuff I just follow the normal service schedule. No mechanical problems at all except 4th gear is a little reluctant to engage now, though I believe this is mostly due to years of shifting into 4th a bit briskly and no fault of the gearbox oil.

Talk to Michael at Autosphere for Red Line and Motul stuff.