Hah, that reminds me: So my setup is already the above-pictured 20% underdrive Stillen crank pulley, and NST's 10% overdrive alternator pulley. I've been trying to figure out what belt length to use with the AC deleted (which I haven't done yet, but I can test belts). I've been trying to do the approach (was it Forged or GTM? some builder did it in some past thread) where you delete the smoother idler pulley closest to the AC, and the one that's dead in the middle of all the other pulleys: Crank -> top-center idler -> steering -> alternator -> tensioner -> Crank. Whoever did it before mentioned Gates K60500, but it was too loose by a lot (probably due to the underdrive crank). I've now tried K60480, and it was too tight (couldn't even get it on). So next up, I guess is K60490
Are you doing that same belt route? Of course your lengths may not match up with mine if you have the stock alternator pulley.