On my Ruby version, I had a Tropius and a Walord as my HM Slaves. My Tropius had Cut, Fly, Flash, Strength while my Wailord had Surf, Waterfall, Dive, Strength.
In Firered, I only had 1 HM slave with only 2 HM moves. I used an Oddish because it could learn Cut and Flash. The other HM moves were...