The pots on my H1 500 Kwaka were pretty seized on and corroded.
I left it in the frame and put a ratchet strap through the exhaust and intake port, then around the top frame tube. A little tension, lots of lube and after a few days, the most stubborn one pulled free.
Won't work for all of them no doubt, but quite satisfying when they popped out.
Great, you could use titanium studs. Not sure how they react to aluminium, but stainless is worse than steel for dissimilar materials. Another old fashion remedy would be to paint the bare studs (new ones).