i read that the front speaker size is 6 1/2" and the rear is 5 1/4" but do they need spacers or will it fit right into the door.

 

If I remember correctly it was 5 1/4 front and 4 rear. 6 1/2 and 5 1/4 will fit upfront but most quality midranges will require a spacer. 5 1/4 will fit in the rear but depending on the speaker it may take some work. I'm running Boston Z6s upfront and 5 1/4 pros in the rear. The pros take more work than its really worth to get them in the rear but I already had them so they were used.