67-72 rear speakers and subs??

[bigbadchev72]

I have a 2wd 68' shortbox I am currently building, it is stripped down and getting ready for paint. I have purchased enough dynamat to cover the while cab floor and back of cab. I have removed the ashtray and re-worked the metal so that I can install a double din head unit with navagation and bluetooth and I am planning on running a 6.5" speaker pods in the kickpanel location. I am curious as what to do for rear speakers and subs?

I am running a factory bench seat with the gas tank relocated to the rear so I will have a fair amount of room behind the seat.

Lets see some pics and hear some options please.