drilling rear disc rotor for 5-lug

[83GTvert]

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[Caprisvo]

I used to have that set up, but we welded the old holes up before redrilling. Didn't have any problems.

[Zephyr 351C]

I ran my 4-lug drums re-drilled to 5-lug for a long time before replacing them, and I didnt have a problem with them, until I wore all the lining off the shoes, and continued to drive the car until the next payday.

Some of the willwood brake kits fit two, three, maybe even four different bolt patterns. Thats 10-20 holes in the hat. I dont think you have anything to worry about.

[Mumfts85gt]

I agree with Zephyr 351C. I don't think you have anything to worry about. I looked on http://www.discbrakesrus.com/make/ford/mustang.htm#brakerotors and found some rotors.
http://www.discbrakesrus.com/make/ford/rearplain54036.jpg