Grk is right on the porting, a 50mm could be used but it will only work properly on a drag ported motor especially with a lectron.

I would recommend another builder for porting but we all know how that goes.

One last point, though everyone is limited by their budget, a motor is an air pump system and you can not just buy one piece have the rest mis-matched and expect highest performance.  So buying a 50mm lectron and slapping it on a stock port motor, with a Q V-1, some v-2's and a large filter won't get you the highest performance on the drag strip or on the trails and ou'll be pissed b/c you spent good money and you're performance went down on both ends.

If you want a drag only motor have JH port the crap out of it and run a 50mm lectron.  If you want to drag & trail/dune then get a aggressive dune/drag port and get a Vm44, or a HV44 lectron (they'll cost you about the same to get and set up in the long run). 

You have to start with the end in mind otherwise you'll be chasing your tail all over the place continuing to spend $$$ until your happy. 

You seem to be like the rest of us not happy until you've got the max performance possible for what you want to do so figure out what you want gather the parts.