Wow that spread sheet is amazing. It has almost any engine on the market and they are all sorted in order of [accurate] all-up weight. One thing I discovered the other day, that Taurus 52 many times requires stand off's in addition to the radial mount. That may add 2-3 ounces more depending on how much you need to stand it off and what you use to make them (alum, hard wood, ply etc).

Also that Brillelli 46 is so light that it might cause balancing problems making some larger planes come out tail heavy. Not that's a nice problem to have......reminds me of the phantom BME 55......