Reverse light illuminates with Brake 1995 k1500

[TorchRed77Vette]

Got a good one for you guys. So here is the current condition I am observing:

Headlights off, brakes and blinkers work fine and correct lights illuminate.

Headlights on, when brake pedal is applied reverse lights take place of brake light and blinkers blink fast (reverse lights blink) as if a bulb is out. No brake applied, blink correct speed (reverse lights again).

Background info. New to me truck, trying to figure out what's been done to her. New brake switch. Brake Relay is "bypassed" with a jumper wire essentially using brake switch power to illuminate lights. Checked load side of relay. No power. Power only at switch terminal. Brake fuse checks out. Cleaned rear light ground terminals well and secured.

Could this be due to the notorious brake light circuit board? Or is this all due to the relay hack?

 

[TorchRed77Vette]

Update: fixed the relay jumper hack/no power at fuse block. Pinched wire.

Lights have same condition. Running lights might be a tad dimmer now (might just be me though).

I hate to start throwing money at it. Anybody know symptoms if bad circuit boards? I wouldn't think that would be it because both lights exhibit the same pattern.