Yes, bottom ball joint. They can be a swine, there are various methods to remove them using proper tools, sometime heat helps, and sometimes CAREFULLY tapping a big screwdriver in the slot in the hub (probably at the back) to widen it slightly can help. Also pressure downwards on the suspension arm while hitting the hub (again, carefully) can release their evil hold. If you can get a lever above the thread to push down on it, or better yet access with a hammer (maybe using an extension bar on it) you may also get it to move. Unscrew the nut until it's level with the top of the thread before trying either of those methods though.
Hate to say it but you will need a ( inexpensive) tool to change that ball joint .
The best way to separate a taper ball joint is to loosen the nut so it's finger tight but leave it on the threads to protect it , then belt the knuckle at 90 degrees to the ball joint . What you are trying to do is momentarily deform the tapered seat so it releases the joint . I assume from the damage to the threads you were hitting it on its end ? That's never going to end well .
The fork type splitters are a waste of time too as they always fuck the boot which is an mot failure anyway .
Quite pleased with myself that I did work through all that list pretty well by myself. Wasn't making a complete hash of it...
Was a fork type splitter, yes. Boot got duly fucked, yes. Then temper was lost, and, ah well. Ball joint socket ordered to fit the new ones.
They were easy compared to the rh driveshaft. It was seized in the mount, and the mounts dowels onto the engine had corroded hard, so the driveshaft wouldn't slide through the mount and the mount wouldn't budge either.
Happy days. Gearbox is off,I'll go back to it later.
Thanks, as ever, for the help.