I'm replacing the steering bearings with tapered rollers, but not sure if all models use the same sizes. I measured and found I need a 48mm x 30mm and a 48mm x 25mm. Bearing outlets don't stock this size, so I turned to ebay, numerous adds for them, but some say fits 75-80 models, others say 70 - 80 models, other say 73 models only and yet others say 75 and 76 models, so I assume there must be a difference, And of course being ebay sellers, the sellers either don't know the size or can't be bothered answering questions. I'm aware some later models take 47mm OD bearings and the 74 TX has some imperial sizes on some parts, ie, the master cylinder. Can someone comment.