98 vs. 07 Driveshaft Hump question (interior)

[matrx10503]

I am trying to get a speaker box for my truck and the box says for 1988-1998 GM trucks.......I have a 2007 (but has more 2006 or "classic" style features/insides) So it is the classic style...not the newer hybrid style.
(some people will understand what that means........)

Anyway........I just wanted to know, how big of a difference is the side (specifically driveshaft hump) of a 88-98 extended cabs and the new ill say 05-07 style extended cabs.

If anybody could take a picture of under their back seat in a 88-98 that would help be greatly and I can compare.