Paul, attached is a photo of Geir's housing.  There is a tension bolt
hole in the way of the p port.  On my housing this was blocked off
and only ran half way through the housing.  Are you familiar with
this?  Is it an early permutation of the 13B housing?  It would have
to be blocked with epoxy.   I am thinking that a good plan would be
to fill it with epoxy before boring the port.  What do you
recommend?  Jerry

I have no idea the year they changed.
Yes I think that would not hurt. Actually to go one better
turn an aluminum rod that just fits and bond it in with
JB Weld. Clean the hole of course by running a drill through
it.