An untouched head will measure 4.000" thick. At the front corner on the manifold side there is a small step...I just checked an 848 casting head and found it to be .090" deep. That step can be seen clearly in this tech tip:


https://www.stovebolt.com/techtips/milledheads.htm


As for facing I would suggest only the minimum required for cleanup rather than inviting other issues.



1952 1300 Canadian 1/2 ton restomod
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