Thanks everyone

Steve - //www.minimania.com/part/CDU1563/Classic-Mini-o-ring-For-Dam8706-Also-Used-On-Rod-Change-Drive-Shaft - I change them regularly.

Replacing the pot joint as a complete unit into the diff without a driveshaft fitted is the best way of doing it - you can drive it home straight, feel the engagemant click better, and if you've split the two halves to do a seal you can reattach the boot without struggling.

Sliding the axle into the pot joint is then a doddle.

For any O ring you can come up with, Zatkoff seals and packing will have it, and in Viton. They are in Farmington Hills Mi. They do have a minimum amount per purchase, I think around $40.00

I replace the output seal then oil the pot joint OD and push it in place once the splines engage I use a old broom handle and insert it into the joint ID and tap the joint in place waiting for the ring to engage. Since I have yet to find a source for the tiny o ring that seals the axle to to pot joint I smear a little Ultra grey  around the shoulder after greasing the splines then insert the axle complete with CV and boot. Then you know what goes next. Keep forgetting to ask if jeweler has watch back O rings in correct size. Steve (CTR)

Looking forward to the experts responses. My brother is a hobby machinest and I'm sending him an axle to get a take on the NLA inboard CV 18g1243 tool, unless someone has one for sale?...

What is the best sequence for installing a new pot joint? Clearance on the left side is tight. Can the pot joint be pushed onto the out put shaft, and push the axle into the pot joint after? Or should the axle and the pot joint be pushed onto the transmission output shaft as a unit? It seems there is a possibility of damaging the oil seal in the pot joint by doing them separately.