Rear diff notch

Alright so i was looking under my truck the other day because i noticed a leak and saw my diff leaking, noticed it was coming from the top and was confused so i removed my bed to have a better look and my rear cross brace above the rear diff center pumpkin was rubbed through and had a hole. Not sure how far ive lowered so far but atleast a 6/8 or more. I was going to just cut it out since i already have rear bracing but realised it supports my gas tank can i just do a step notch in the center above the rear diff and cut out the center so it stops hitting my diff? I also had the idea of full step notches instead of the djm c notch and bridgebars and relocating my gas tank and just removing the center support altogether, any ideas?