My 53 Chevy 3100 OEM had the three speed replaced by PO and an SM420 installed to the closed drive line. My bell flange collar is slotted from bottom bolt to bottom bolt. I think this is wear from the crossmember mount wearing up through the flange. Am I correct or are they slotted for a reason?
flange


1953 Chevy 3100
261 and SM420
53Chevy 3100
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