The two things that make Pantera cross pin removal 'interesting' are- wear of the mild steel pin which raises a burr around the pin and also creates an egg-shaped depression in the pin and the lever. Sometimes corrosion intrudes as well. That whole 50+ yr old area is metal-on-metal & is never lubricated- maybe not even at the factory. This all makes it difficult to force the pin out- which ideally is a simple finger-push fit in the lever.
Look closely at the exploded parts illustration to figure out exactly what you're dealing with. Some of the levers are steel and a few are cast steel which breaks like cast iron if forced too much. Can't remember which yours is. Because of the pedal forces involved, broken cast levers don't weld repair.
If the pin simply won't move either way, and you can't get a thin saw blade or grinding disc alongside the clevis to cut the pin in 3 pieces, I suggest removing the pedal plate, lever, shaft etc and DRILL the pin out in a mill or drill press, before you break something spendy or set something on fire. If things ARE that badly worn, after its out you may have to weld & redrill or bush the pin holes- which would be a second nightmare to do in the car. I use hardenable drill rod for replacement pins so there's no reoccurrance. Good luck.