hello i have a 06 si an 2nd an 3rd are grinding so im going to rebuild it an was looking at the sets they have but im not gonna spend 4400 on them so i was wondering if anyone knows if a 5spd 1st gear will work in the 6sp

 

The mainshaft 1st and 2nd gears are built into the shaft and are a different ratio than the 6 speed. If you want to go with the 5 speed 1st gear, you will need to replace countershaft 1st and 2nd gears along with the main shaft. PM me for pricing on the 6 speed sleeve sets.