Removing large gear of C&P

I think that would be a taper key with its gib head gone. Pulling out would just tighten the wedge. Either drive the gear back on the shaft and hope the key doesn’t follow (first apply and let soak in some penetrating oil), or drill and tap the key and try to extract with a slide hammer, or as last resort drill and chisel out?

The proper removal technique is to remove the “Head Cam” from the other end of the shaft. Then remove Main gear and shaft as an assy. With a rosebud tip on an acetylene torch, the cam can be heated to where it should slide off. It may also need to be beaten of with a sledge hammer. At this point, it is a 2 person job. I recommend a large slug of brass with a threaded rod handle. Hold the brass to the cam and hit the brass with the sledge hammer.
There is a lot of weight and heat going on here to remove this. it is probably a bit much for a hobbyist.
Professional help is a good idea here.
Why do you want to remove it in the first place?

I have a question about this. Had to go look, my early New Style does not have those two holes shown in the photo. So I’d have to follow what is said above—-but aren’t those two holes for a gear puller?

a gear puller could be tried on this press. But, the puller would only be a 2 point puller. these get real unstable under high load. A 3 point puller would be better for the load needed here.The gear is not drilled for that. someone prob put those in at some point, as i do not believe they are there from new. my 2 old kluges here do not have them. the frames are pretty much the same. Kluge simply took hand fed C & P and made them auto fed.
the gear is pressed on very tight. It is only this pressure that holds it on, and in place. The head cam is made to come off easier. A big 3 jaw puller works. If you can find one. I highly advise getting some heat on it.. Heat around the very perimeter, Not nest to or around the shaft