You got the wrong seal in your kit. By 57, all the blocks were machined for the rubber (neoprene, maybe?) seal, and the groove in the block and main bearing cap isn't machined as deep. There's no room for a rope seal to work right. Either use the 2 piece lip seal, or machine the block for a full circle type. I believe Best Gasket is making a neoprene type seal now.
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!
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