America_Transcription_alt.dorico (2.5 MB)
First I added the 6/8+3/4 to measure 67, so that when I changed a measure before, it would not try to ripple through the rest of your arrangement
Then I went to measure 65, which was the start of your combination time signature, thinking Doprico might object to a change in the middle of the pattern, and I set measure 65 to 6/8, which would then ripple through until it hit the time signature change in measure 67.
I admit, the first time I tried this, because I didn’t get the time signature in 67 to stick (I suspect), I also had Dorico quite on me.
I hope this approach can help you out @BenjaminRoberts .