I would like to swap 5th gear on my YS1 transmission, just so the engine runs slower and quieter on the highway. According to the service manual, the whole main shaft and countershaft assembly come out as a cluster after you open the transmission and 5th gear is the first gear that comes off. So, I wouldn't think it would cost all that much.

However, both shops I tried in Ann Arbor, MI want $500 to $600 to do the gear swap, and this is with the transmission out of the vehicle. Does anyone know of a shop in the Detroit area that specializes in Honda manual transmissions that might do it for a reasonable price?