tire compound for sts focus.

[MEDUSAzx3]

ok after the lapping day shredding the crap out of my street tires. i've decided to make the jump to a set of dedicated racing tires.
so my biggest question is what compound is legal for sts? i know i'm limited in wheel choice (planning on some light 15"s as thats the smallest rim a focus came with that'll clear my brakes)
bit i'm a bit confused on the compound rules.

[Kiesgen117]

well to start with 140 tread wear is the lowest allowed, 7.5 in wide rims max, so falken rt-615, toyo r1r, bridgstone reo1r, dunlop derezza, kuhmo xs, are all good options.

[MEDUSAzx3]

ok. i'll aim for some 7.5 inch wheels with the kuhmo xs tires on them
looks like thatll be my best bet for grip.
thanks man.