I need a tool like this
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To make two D-Shape holes like this
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Note the size I need is the 24 pin (larger of the two measurements)
So I can mount this.............. in the firewall
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Does anyone have any idea? The tool pictured is WAY too expensive for the two holes I need to make.
Any ideas on make a clean cut likt that in the firewall without a tool like pictured above?

To make two D-Shape holes like this

Note the size I need is the 24 pin (larger of the two measurements)
So I can mount this.............. in the firewall

Does anyone have any idea? The tool pictured is WAY too expensive for the two holes I need to make.
Any ideas on make a clean cut likt that in the firewall without a tool like pictured above?
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