I think the 7 ch should have enough terminals. Connect the IBE to the retract port, one of the regs to battery and the other to an aux channel. That should leave you with two ports unused. What else are you driving in your set-up??
I have the 7-channel Futaba, but the last channel in the sequence is 7/B, so it isn't 7 channels and then another battery slot. Guess I will put one batt on 5 and one on 7 with IBEC.
Or wait for the 8-ch.
Good info on the prop and carb setting. I have a 17x13 APC Pattern and wonder how it would do vs the 17x13 standard. Thinking of running break-in with something with a little less pitch, and I have the 18.1x10 so maybe use that.
I got the Graphtech LG and wing tube today, so the completion is definitely in sight!
But I also couldn't resist the nice weather today and was out flying the Focus Sport.