i did !!!
for 2 seasons , i bought 3 upper gears and three lower gears , not sure off the top of my head what gears i have but i did the math and tried to get it close to stock .. lets make a long story short , i am putting the 9th drivers back on this year !!!sled never was the same with the 8th drivers , by the way are you going with anti ratchet 8th??? if not .. send them back and get them , if you need to get your track punched and clipped i have the number for a guy in indiana thats doing it ... but with out the antiratch driver the track kept ratcheting (sp?) i had to run the track so tight i couldnt get my finger between track and hyfax , and once i got it to stop ratcheting by the tight track i couldnt adjust my transfer rods or the track would start slipping again ..... sounds like we run the same setup (benders) sorry for the not so good news , if you need any help let me know !!!!!good luck