The later model 235 main bearings with the locator tab at the parting line of the cap and block can be used by modifying the block. The 54-55 year only 235/261 bearings with the locator dowels in the upper bearing can be very difficult to find. I've modified blocks to use either style of bearings in the past, so I know that procedure works.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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