should all four lights on the rear be lit when lights are on, and then when you go in reverse the 2 center lights get brighter?

No. you probably have a bad ground connection at the rear lights if that happens.

The two outer all red lights are your brake, signal, and tail lights. The inner two are only for backup, and only the white portion lights up when backing up.

can you tell me what color wires should attach to the reverse light bulbs? is it only the light green wire that suppose to connect?

There's also a black wire to each light socket, originally.

so, reverse has black and light green, and the outer lights have two wires plus the black.

can you tell me what color wires should attach to the reverse light bulbs? is it only the light green wire that suppose to connect?
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