You need to be aware that the main bearings for that year of 261 are almost nonexistent. It's possible to use the later model mains, but you'll need to do a little grinding on the block where the anti-rotate tabs fit at the parting line between the block and the main cap. PM or call me for the right part number mains and how to make them fit.
Jerry

Last edited by Phak1; 03/13/2025 11:59 AM. Reason: Typo
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