Suggestions for greddy oil pan..

[Annoying Eric]

Well..... I picked up a greddy oil pan from my friends shop.. Looks sweet and everything. The problem im seeing is that greddy put some retarded thread size in it and definitly wont match with my autometer oil temp guage.. I have already brought it into my machine shop, and have sat and thought about...
Here are my options:

Tap out one of the holes using the bottom of the thread as the lowest point making sure not to make the new hole too big so that it starts to hit the bottom point of the pan. (Might not of explained this right)

Tap a hole into the rear of the oil pan and risk having fitment problems with the oil sump.

Not install my guage..

Does anyone have any of suggestions or know anyone who has had a similiar problem and solved it some way..
I have full access to a machine shop and actually know what i am doing...


EDIT - The reason why i cant just tap the hole bigger without it being a big deal is because the auto meter guage probe has very large thread and the holes in the pan are near the bottom of the pan...