Replaying LeafGreen

So I decided to pull out the old LeafGreen version and decided to try and play the game with one battler (Squirtle). Obviously I will need a Pokemon to learn HMs, but will not be using them in battle. The only other Pokemon I will catch will be shinies if I see them, but in all it will be a one-man show. Just wondering, has anyone tried this at all? If so, any advice?

I've tried this circa 1999 on the original games. I think it's pretty fun, you'll be vastly over leveled and Blastoise is a helluva tank so you should be fine.