I am using the stock 13b oil pan along with the cci motor mount.  The stock 13b oil pan has 3 motor mount holes that are utilized when mounted in the car.  In aircraft application with the cci mount only two of the three bolt holes are used.  I am looking for the best method to seal this extra hole.  Are some choosing to weld this hole (although this is a very important piece to the bed mount and needs to maintain a good seal, and a bad weld may warp the thin pan)?  Or would a locking nut and bolt with some type of gasket maker do the trick?  Possible some type of expandable plug like the ones used in a boats?  Not sure what to do looking for the best answer.

Thanks
Keith
RV-7A
13b
With all of Tracy's stuff
CCI Engine mount