hello from New Zealand, 18 spline head ache a833.

In my opinion someone installed that transmission on a motor that wasn’t drilled for a 4-speed so they had to shorten the shaft. If it were my car I would ch the crank and change the input shaft.
makes sense i was told it came from a 426 but anything could happen

the end looks machined well and centered tho, changing the crank is big job, more modification to the input shaft would be preferred,

is it a thing to fully prep the end, and weld an extension on and machine that down true, proper full pen tig and a cap and fill of flux core mig?

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