Yeah I just got my 2Gallon kit so I can do inside and out. It is supposed to be the perfect amount, and like ELShafer said, you should have enough left for the heavily trafficked areas inside.
Complete rebuild axle/engine/everything swap in progress: Building stock width 44's with 302 from 01 Explorer. Motor has GT40p heads, Cobra Intake, and truck cam. Running A9L EEC IV stand alone engine from late 80's-90's Mustang GT. Big Bearing NP435 married to NP205.