Just a standard factory finish, lt blue bottom two shades of green overall. Plans really show 2
.25's with plain bushed engine in back. Too much weight in tail with 4 stroke for me. Plus you may need to minor redesign to accommodate one in the rear. I know of a larger one(2 .60 size engines) that the guy put 2 .70 4 strokes and he said he needed to modify the tail somewhat.
Work has slowed as I got a hair for something else but I've started to glass the rest of the plane and will continue to work on it. I know it's not best I build a couple of planes at once.