When I spun the cam dowel off my 496, I found out that the damper that was hell to get on was even "heller" to get off!!
We used a oxy/acet torch to gently warm the damper, but after numerous tries, it still wouldn't budge.
So...off to the fridge for a bottle of "ice" water.....heated the damper up again and shoved the open bottle of water right onto the snout of the crank and gave it a good squeeze while we had a lot of tension on the puller.
SNAP.....it cracked loose and off it come...albeit slowly but it came off.
Next damper was honed a bit to get the fit right.