Go with the 10 inch rims for sure. You will need to notch
the frame to get the rim under the car. A 5.5 back space
will work very will with a 10.5 tire on a 10 rim. We have
also run a 29.5 x10.5w on w 10 inch rim with a 5 in bs.
That stuck out a little bit. I am not sure if it would fit
with the 5.5 bs though. Chris Chow has gone 1.35 60
with 9.17 @ 149 with the stock suspension with the previous
stated combination.