When I did my RedTop swap, I fitted an Excedy TYK-6914HDB (Heavy Duty Clutch Kit). Feels perfectly normal, though there's a non-heavy duty option listed too on the Excedy website for the RedTop MR2:
You can find it listed @:
http://www.exedy.com.au/clutch-finder(Go to the 1998, {149km} model) - Listed as 12/97-10/99, @d Coupe, RWD, AT/MT, (Japan) .
The page then confirms the selected vehicle as : TOYOTA MR2 SW20 12/1997~10/1999 3SGE 1998 cc I 4cyl 16 valve DOHC PETROL MPFI 2 Door Coupe RWD Auto Man