How to mount 12 or 14 cells in stock revo?

The battery block is on the right side. Here's what I found, it's slightly out of balance to the front right corner by 3.25 ounces (1.7% of total 11lbs 10ounces). The rear is off balance to the right side by .3 ounces (.16% of total 11lbs 10ounces).

LF 2lbs 4.74ounces ----------- RF 2lbs 8.01ounces

LR 3lbs 6.8ounces ------------ RR 3lbs 7.1ounces

Once I switch to lipo and basically cut my battery weight in half, it should be pretty close to perfectly balanced, or slightly heavy to the motor side. With the (14) IBs I can't tell any difference in flight, so I'm thinking that the lipo shouldn't change things either.