h55s are notorious for having issues with seating the shifter into the right spot in the fork assembly. I have heard of this before and it was always that the shifter was inserted in the wrong spot... You have the correct H55 shift lever and are not reusing the 4 speed one right? email me with more questions as I have two of these and have done this a few times...
Kraig Hamady - Encinitas CA
1981 HJZ(BJ)44 RHD - Linked, 1999 100, ready to be built up, 1972 HZJ40 - Work in progress