there are lots of considerations here but i think cost is going to be a very big one. how many people are going to be willing to drop $150 on a conversion for a car you can get for $150? lol. "that if yodog or i put out a conversion, cost for us would be well over $100 lol.."
to optimize teh flex and layout the stuff better, it will require a new main chassis, upper chassis, probably motor mount and layshaft carrier and any other bits needed to do the flex thing.
the simplest thing is probably going to be an e4d style upper chassis with a lower chassis that doesn't have the big ass hole for battery removal. optional for me would be a new front shaft carrier, because the stock one seriously limits moving the battery forward which is what needs to happen to stop mangling those stupid side bulkheads we have to cut for lipo/brushless mounting.

i was thinking of doing a sort of 12th scale pod for the motor. would be semi rigid, but would require widening the chassis slightly to keep strength with a big ass hole where the motor is. it would be suspended between the buklheads and a middle bulkhead . this would be more brushless friendly, and lipo friendly. pecking at it slowly. still learning after all. im sure yodog has something epic on his board.