RE: Converted Y/A F-16A to from DF to pusher
Well @ 12> 14 lbs. the YS-45 is not going to be enough-
Assuming your fuel tanks are going to be near the CG (like the CBM F-16) the difficult part is finding an engine with enough power that can deliver fuel efficiently that distance- An OS-91VRDF in a Dynamax or Ramtec fan only has about 11 lbs. of thrust so to fly a bird that heavy- you will need something big!
I am sure others will chime in-