rear taillight not working after rollpan installed

[2dryukonlv]

need help cant figure why my tailights on my 94 yukon 2 door not working tried google search also..
any info is helpful.. they were working before i installed rollpan
okay i installed a steel rollpan and disconnected tow hitch plug and hitch itself
and also disconnected ground wire from the frame since i needed to cut frame far back..
as for the ground grinded frame with grinder and reattached ground wire.
but as for my lights 3rd brake light works front lights and turn single lights in front work only.turn signal lights blink fast.the truck fuses are all good pulled every single one . taillight blubs are good not blowed.. so brake lights and taillights not working also the license plate light not working.
I tryed another stock taillight doesnt work .replaced headlight switched and brake pedal switch. tryed pluging trailer plug back to truck and grounded too and still dont work.. i pulled out light tester and no power to license plate plug or trailer hitch plug. any opinions or input????

did i ground the wire wrong?its grounded to bottom of frame next to gas tank..

 

[Gzes]

Possably because when i welded my rear on my 2dr i had to ground right next to where i was welding to get good contact

 

[2dryukonlv]

so like up behide the roll pan attached to inner quarter panel where welded?