BB 727 to A518 Conversion

Holy Cow guys! That is a lot more information I figured I would get from this post. Thank you!!

it kind of stinks to hear that I cant use the BB 727 case for the A518 tail end.

AJ brings up a good point of just changing the rear gears to get the mileage. However like you said you ruin the vehicles take off gear at that point. I was thinking of using a 3.21 gear or maybe 3.55's. However the engine would at least get a 4 barrel carb. Maybe down the road the engine would be tore into for a bump in compression and a little bit more exciting cam. But the torque curve of the engine would definitely need to be studied to find out which combo would be best.