I made a tool out of a 13m socket to remove the speedo pinion gear nut, got the pinion gear out now i cant lift the drive gear out of the hub. It's been soaking for days in Pen oil but no budge. Any tricks? It doesnt even move at all.

Yes they can be a pain. Could flick the big seal out & apply some heat but not enough to turn things red or dripping alloy. Then carefully grab the teeth with long nosey pliers & twist left & right. Another brutal thought is if you were stuck maybe you could drill two holes through the plate for a long skinny punch to puch it out from behind. Think bit of heat will do it though, with seal removed. I've had some bad ones over the years. By the wayy--& i'm sure you know--the drive plate will be rounded out--stuffed. Maybe that drilling idea isn't good as there is a steel center meeting the alloy brake plate in there somewhere. Just be careful. Not got one handy for me to study.

I’m wondering if that steel bushing that the drive gear spins on can be knocked out out of the aluminum hub? Maybe heat up the aluminum and knock it out? That sucker won’t even spin

I would use a pick to get the seal out then use a Robertson (square) drive that fits inside the gear rotate it back and forth maybe that will free it up use some heat if needed 

Finally got it with heat and a rivet gun with a chisel set. Once i got the gear to rotate, it free'd up and I was able to pull the gear off with needle nose vise grips. Cant believe I didnt maul up the gear. It prolly hasn't turned in 40yrs.

This is a timely post...I have the same problem with the hub soaking in evap-o-rust right now.  

Does anyone know if a tool to remove the worm gear holder is easily purchased?

There are a few threads on here on how to make one out of an old socket.
This one is on eBay I don’t know if they ship to the U.S. or if you are in the U.K.
 

That's good news, they rust in pretty good. When you get the new drive plate & fit the wheel, be careful to line up the plate ears so they don't end up bent away & then not drive the gear. Ears between the raised bits of the hub extension.--as i'm sure you know.