Buy all new belts.
From the 1970's your belts are over 30 years old, perfect or not. Think of the age of the material as you are trusting your life to it.
Maybe now is the time to put those three point/four point belts in you have dreamed about. Even NOS factory belts have outlived their useful life. Check with the Pantera Vendors, they have lot's of great options for you. Just don't put another set of 30 or 20 year old belts in.
Mitch
PANTERA INTERNATIONAL
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