Drilling and tapping the crank is no big deal.
Use progressively larger bits. Start small and don't go up to big on the next one. Then run a tap through it. Then run a drill through the front 1/2" of threads.
You can buy a bolt and washer at any speed shop, or just buy a grade 8 bolt and washer at Lowe's or Home Depo for lots less.
'51 Chevy 1/2 ton w/'62 261, HEI, offy, fentons, dual carter/webbers, t-5 & 12 bolt posi
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