Slant block to 904 bell-housing bolt specification

ConfusedMuchOfTheTime said

I did slot a 3/8 UNC in there just to see and will try again with light tooling as only used my hand before. Def grade 8 7/16" x 14 TPI UNC Coarse Zinc Hex Bolts Part Thread High Tensile Grade 8 AS 2465. Looking around the web tells me the spec should be 7/16 but will fiddle around again.

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So, the 3/8 UNC spec threads in nicely now with a bit more torque than my hand :) and some WD40. Weird though as all my research has come up with a 7/16 UNC for that hole and my 7/16 shank does not even bite the threads. Oh well, you live and learn.