I'm piecing together a custom oil pan for a 20B engine, and am trying to
figure out where to put a dipstick.

The stock dipstick lands toward the "shallow" (forward) end of the pan, and
won't do the trick on a sloping bottom intended for a nose up (tail-dragger)
attitude.  anybody put in a dipstick near the back ("front" cover) end of
the engine?  Probably applies to both 12B and 20B engines, though in the
longer 20Bs the problem is aggravated.

Tom Kendall