Will 2 Alpine type R 1243d Subs fit under my back seat of a 2005 gmc sierra?

[bigM]

and what amp should i get? if those subs dont fit then what will? i have an ext cab truck and im plannin on making my own box to go with the subs. i just dont know if they will fit.

 

[knuckleheaf27]

ive never seen a pre-fabbed box for 2 12's, just 10's....... if you know someone who builds a good box you may be able to pull it off....