You can do it without the tool, but you may damage something. A cheap steering wheel puller with the correct bolts will do the job. Your gasket is Threebond 1215 or similar.
You should have checked stator output before ordering parts.
Thanks for the tips!
I figured I'd roll the dice since the rectifier seems like a descent upgrade - I like the Li battery, the bike starts way better with it than it did with the AGM batteries I've had in it before. I would've had to pull the bike apart to this point to get to the stator connection anyway, and the rectifier wasn't particularly expensive either so all I really lost is a little time. I ordered the new battery as well. Hopefully good for another 20k miles at least
regarding the gasket - I found this on the motowheels site:
https://motowheels.com/i-8184836-exactfit-alternator-cover-gasket.html - I've never used liquid gasket before, is there an advantage to it over something like that?