My fastest IM swims were 1:00 and 1:03 at IM Florida and 1:08 at IM Couer D'Alene. All three were wetsuit swims and I didn't kick at all and I have no idea what my spm is. When I know the race is certain to be a wetsuit swim I do all my long sets (anything over 400 yds) with a pull buoy. I also focus a lot on developing a strong pull by using paddles as I personally believe open water triathlon swimming requires it.

This may not work for everyone but it works for me.