Your plan is what I did last summer. I brought them ALL home in pickup, and sanded in my garage on a 4x8 sheet of plywood set on stands.
Following the directions is good. What I found, and others can chime in here, is between the 1st and 2nd coat, while directions say to just apply the 2nd coat no sanding, I found a quick wet sand with 400 grit was needed. Otherwise I did not get a smooth surface with the second coat.
So far after about 9 months, it is looking well, working well etc. I also did a removable stairs engine cover with US instead of
varnish too. I am hoping this will stay a bit long on this high use area vs spar
varnish as the rest of the interior was redone in.
Marty