Why not either mic your amp (continue to use it as a stage monitor) or if you have a line out run a line out through the front end?
Depending on the venue (I use the same amp regardless) I'll either just run out of my amp, or mic it or line out through the band P.A.
I'm just running a tight little Rickenbacker TR35B, but she's a powerhouse when I need it. See pic.
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...L