My plan is to remove all of the stock system and putt in a new head unit, 6.5" and 4"speakers, and an amp to power a bass tube which will be in the t-top holder. My questions are;

How would I wire up the rear hatch speakers since the head unit is only 4X50W?

Could I wire the sail panel and rear speakers together or would I be better off with just four 6.5" speakers and a sub?

 

i would just do the 4 and sub. that way you can just bypass the factory amp and you wont need to amp your speakers. i have 4 6.5 db drive speakers and a phoenix gold sub. the sub will block out the rear speakers anyways.