Well it's finally out !
Tried heating (nope), freeze spray (nope), belting it with sized drift (nope) & eventually called mechanic friend who produced portable hydraulic press thing he uses to pull bits off combine harvesters etc when they break down out in fields. That wasn't deep enough to go from one side of frame to the other so we slung the thing in the back of his van. Back at his garage (the most southerly one in Scotland) he drilled it out enough to weaken the spindle then tipped the engine & chassis on it's side & slapped it into a 10 ton press. It only needed 8 tons of pressure to come out so that's all right.
Back home today I see that the needle rollers in the drive side are completely knackered. Rusty & solid with crap that's got past the seals. Spindle is now scrap too so I'll replace the whole lot & fit a hugger.
Might I humbly suggest to those of you with time on their hands over the winter that removing your bike's swinging arm spindle & slathering the ******* in grease might save a lot of grief later on. If you get stuck I know a good man with a press who can help.