Apex 19x11's on all 4 corners, with S550 15in prem package 6 Pistons Calipers on a 2010 GT. Tons of room.
I'm running 305's on a 11in wheel (a little wider then yours) and they fit inside the front fenders with a small amount of Neg Camber. ET52 Offset w. a 15mm spacer works for the front and allows them to be moved to the rear with no spacers, hence the extended studs.
I recall getting just barely one diameter's worth of thread engagement on the OE wheel studs with shim spacers less than one-sixteenth of an inch thick. No way would I ever bless anything much thicker than that with OE wheel studs. Even 1/8" could put you on the wrong side of "marginal".
Norm
I just measured a couple of studs on the OE hubs from my '08 (it now has the FRPP/3" ARP setup). Looks like there's 1.5" of thread measured from the outer face of the hub flange and about 2.4" overall length of the stud measured from under the head (back side of the hub flange) to the very end (includes the unthreaded starter portion). The hub flange itself is a little under half an inch thick (probably 12 mm).
When I was still running the OE hubs & studs, I remember it being very close to ten full turns of the nut from just barely 'caught' to 'snug', and I lost half a turn from that when the 11" wide Forgestar wheels needed to be shimmed slightly (0.025" DIY spacers) to eliminate a minor tire sidewall to strut rub.
Norm
They're the small-hex (17mm?) open-end nuts that should be shipped with any Forgestar F14 wheel. Got mine through Vorshlag.What brand of lug nuts are you using? I'm planning on switching to longer studs if I ever need to replace bearings.