Ford F150 - custom box allowing rear seat to still flip down.

I drive a 99 f150 scab, and am going to put 2 Rockford Fosgate 10's into it. Now, I've done some research, taken measurements and have done some sketching as to what the box will look like.

Now, with a subbox under the rear seat, you can't flip it down. But I need to. So which option would be the most feasible?

a) raise the seat 4", and make a notched box so the seat can flip down.

b) move the seat forward 6-8", and raise it 2" so the seat can flip down.

c) either rig the seat so it flips up instead, or go and find the other style seat for the '99 scab that lifts up instead of down?

i say rasie the seat or find a diff set up. according on how much bass u want u dont need dual 10". if i had it to do over agin i would have went with a dual 8" and still made my own box like i did. i have dual 12" with custom boxes i made and i can still lift my seat but i have an 05

I get more than enough bass out of only one JL 10" sub....