I have a 1968 T120 that I am restoring and it could use some new gear sets (and shafts). I've been researching what I can find and it looks like Triumph made quite a few changes to the mainshaft, layshaft and gears in these three years. One of the changes was to change the gear ratio from 2nd to 3rd for 1970 models. That seems like it would be an "improvement," so I am considering putting all 1970 gear sets in. Wonder if anyone has researched this and has some suggestions as to whether this is a good idea or bad idea?