Made it! I made top of fuse flat 1/8 balsa, as it is closer to scale. cut off ply sides 1/8" ahead of firewall, made a 1/8" piece shaped like front of cowl. mounted engine sideways, tacked front piece to back of spinner w/ 1/16 spacer, then used 3/16x3/8 strips to build the cowl. fit each one, trowel filler, sand it. takes a couple hours, looks good!