nice work. putting together a very similar modified stock 50v. case matched bottom ends, ported as per wiki specs very carefully. piston skirt chopped... all the basic stuff.
havent milled head.. 3mm seems like a shit lot but if you dont have head slapping issues that sounds great.
port map _before_ porting is attached. do the math and you'll see what it'll look like after.
thinking the 16 sha is going to be too big even with a G3, might go down to a 14 just to try it. i also hear you can pop the jet holder/emulsion tube out of a 14:12 sha and put it into a 15+ to get the progression of a 14:12 but the top end of a 15+. anyone got any input on that?
this is all very generic old-tech moby mods but i hope to get some huxpa out of em.