[Boatanchors] pot metal ammeter box

[Dick KF4NS]

I am assembling an RF ammeter (Sangamo 0-3A) box using a pot metal 
box. I will place the meter in the lid but fitting it could be a bit 
difficult.

I am looking for advice on cutting the 2.2" hole. I have plenty of 
tools but nothing to cut a hole that big. The base metal is most 
likely aluminum (non-magnetic). I was thinking of cutting an 'X' and 
then maybe use my Dremel tool to cut the circumference. It is very 
difficult to cut a round hole that way though.  If only it were wood 
or plastic, then the job would be easier.

Any ideas?
Thanks and 73, Dick KF4NS
St Petersburg, FL 33714 USA
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