Thank you ever so much - that is amazing help
@Jelly
I have found a cross sectional diagram which hopefully will attach here - you will probably be able to make sense of it.
I think its a type 1 looking at your diagrams but I haven't had it fully apart yet, and can't be sure.
The guide I bought from Laithes.co.uk talks about seating the angular contact bearings with a tap from a 2lb lump of brass to get the preloading right - but I guess I could just use a 2lb lump hammer when I get to that stage ? There are 2 normal bearings in the housing that support the spindle / pulley shaft. These look like they will need tapping in from above and below the housing - I guess with a long steel rod from below, and something flat from above. My main concern is how to avoid damaging the bearings / races by doing it right. I'm a woodworker and don't have any real machine metalwork workshop experience.
Anyway , any advice on how best to go about installing the bearings would be fantastic.
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