Now this opens things up since it's out of the frame, S&S stroker kit or Axtell big bore, "89" "96" or "97" we love to spend other peoples money. Going to need some headwork with the bigger engine

 

I started by stroking my original Evo with a JIMS kit, but mine was an early one. It was also the thing to do at the time. Later I discovered there were also big-bore kits, which are probably suitable for your later cases. I seem to recall Sputhe did a 106" conversion, also Axtell a 107".

However, modern thinking seems to be that an Evo can give a serious performance boost without such major surgery. You may like to contact one of the HDF sponsors for their recommendations. I suspect head work and matching pistons plus a modern cam will put a smile on your face!