I used one of those sliding framing squares and set it at 1 3/4" and used it as a depth gage.I then cut that section out of the car. After I had it out I re set the square to 1 1/2" and cut the peace that I just removed from the car, leaving a 1/4" "skin" that I welded back to were the piece was just removed from. ( made it look more stock IMO)
I then got some 1' square tubing and cut it at different angles to match the inside of the frame and welded it solid all along the inside of the frame for some re enforcement.
Be sure to cut it length wise long enough to clear the tire. I did mine from the body bolt behind the tire to just past the wheel well in front of the tire.
I used a cut off wheel on most with some saw saw use.( i can cut straighter with the wheel)
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