Someone on hear gave a brief description of what needed to be done; I seem to recall the rear of the crank needed modifying to fit the A14/15 flywheel and you needed either custom rods or custom pistons.

I've given thought to using the E-series crank but the work and cost for me would be better invested in to the cylinder head.

D I've also toyed with twin or single cam head on A14/15 bottom end but unless you're running a race class that requires stock block it would be just as effective to just go with an engine swap. Now of course if you just want to have something unique or as with the Mazda twin cam just to see what you can do then it makes sense.

Tom