Thanks for the comments.
Brian > Am working on next build. Starting with a non-1/72 P-38 to end up with a 1/72 something. Same approach as Slowy Jet. Going thru kits and boxes of spare parts on exploration of discovery of what looks to fit. Two rules for myself are is 1/72 when done and looks airworthy or close to it. Nothing glued or painted yet. Doing cutting/filing to check if parts can be made to fit each other. General configuration now taking form, though can be changed as needed. Like Slowy Jet with H.P.42 basis recognizable, P-38 basis also recognizable though will be way different than a P-38.
Taiidantomcat > Point well made. For engines I did start with 1/72 prop types then it clicked that 1/100 A-10 jets fit well on 1/144 H.P.42. A-10 already cut up with part of it in Zip Jet and tail fitting well on Slowy jet. Under wing Maverick LW missiles are from the A-10.
Bill