Use a 1911 Serpa.
You'll have to do some filing of the trigger lock area on the trigger due to the square shape of a Hicapa trigger guard (1911's have rounded trigger guards). Or you can also just get a Tanio Koba/Guarder grip which has a rounded trigger guard.
It might be a tight fit depending on what gun you have and what Serpa you have (real, knockoff, etc) so you might have to do a little filing to the slide area of the holster as well. I only had to file down the trigger guard lock area, but your experience may be different.
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