So I've decided to go for the reverse gear strategy. I pulled this gear off the PTO plate that bolts on to the end of the S/C and runs the water pump with a regular 3 jaw puller. The problem is the shoulder on this side of the gear. The other side is flat. The answer is the 10mm washer in this pic. I drilled it out, then enlarged the hole with a round file a bit, and finally filed it down to be the same thickness as that shoulder (.156" I believe).