BillS,
The CURRENT and stock center to the fuse is now 10.5". My two cents is IF and I say IF someone were to do this. Move and glue the inboard nacelles center around 6.5", which would allow up to 12" props safely and then move the outer nacelles to a similar centerline to the inboard. My two cents, based upon the Cedar B-17..You would NOT need 40's unless something like LA's. Good .25's to .35's would work and be lighter. The prototype Ceder B-17 has magnum .32's, with inefficient three blade props and will go straight up..and that was before the new fifth engine.
Neil WILL pick up these nacelles again, but YOU asked for it!!
Tee Hee.
Disclaimer...( Too many Lawyers!!!) Cedar, to my knowledge has not tested anything like this, no have I ........Ok..Ok,,maybe someday!!
Good Luck,
Twinman
PS To nchrome on the P-61..Geeze..you guys don't miss much!!! That plane is over two years old,,can't or won't leave in the Garage in Houston in the summer. To date, around 20 flights and three engine outs..not a big deal..other than what happens to my heart rate!!!
(Mental Note)..be more careful of back ground..you would not like to have seen the picture of my bare feet in one post up at the Phoenix build that I spotted before posting...now there is a MENTAL IMAGE!!!