Well found a fantastic way to use the A12 crank into the A10 block
using an alloy bed plate that holds the extra mains which you use
reversed mains to hold the 2nd and 4th mains and take A12 bearings.
Here is a picture of the adaptor used on 3 bearing Ford T flatheads
This is a complicated modification but I was asked by a rallye guy
from Melbourne how he could increase the capacity for rallye driving
as the 1070cc max with bigger pistons is just not enough.
I have though about this before and then just lucked finding this
modification on a banger forums so immediately thought about
our B10 lovers as a way to strictly remain with an A10 but with
270 more ccs which would be a nice original touch.
bottom view
 
and a nice final touch would be to top it off with a twin cam head
carbs, headers and a good 5 speed.