the front need 3 ohm, you can run the 2 6's in parrallelor or in series I forget, but you need to run them upfront. having them in the rear doesnt do anything for the front. so run 2 six on one side to make 3 ohms, then another 3 ohm on the other side/
Rob do you know which (white/purple or white/green) is brk/blk?
i dont remember the colors but if you look at the bulb socket wires going into it, the brake blink is the outer wire that isnt black. the middle one is park.
if you swap the outer wires those 3157 will work with 6 ohm.