Once you have done it a few times and get to know the potential problems it will be fairly quick. I’m down to about 1.5 hrs now.
Critical things are
1. Removing enough oil
to ensure you take level below selector
2. Clean threads on the 4 studs that you have to back the nuts off on. I ensure they are well covered with an anti seize compound
3 Measure the length of thread protruding from nuts before slackening nuts, this is to ensure when retightening and re engaging gears you get it right!
4. Having a splined holding tool to for the removed clutch assembly in a vise whilst loosening the left hand thread nut
5. 30 seconds of lapping is more than you need. Ensure you wash all lapping compound off both faces of the cones!
6 Take note of where the spacers are while disassembling and refit
in same place.
It’s not a hard job once you have the right tools and the holding tool. I bought a 2 nd hand SD 50 from a Yanmar mechanic
app $300 which I made the spline tool from and gave me a spare clutch pach for even quicker Change over!
If you don’t have the holding tool use a couple of bits of aluminium angle as soft jaws in the vise to protect the spline, not ideal but I used that several times satisfactorily before making up the holding tool.
Good luck it’s not hard!!!!