No 6 port hose is not a big problem. There's other ways to make those work

http://www.racingrotary.com/nt/portmod.htm
I've got this setup and it works better than that exhaust pressure BS mazda used (notice the S5's didnt use that shit?! maybe because mazda figured out that it was a bad idea)

There's also a possibility you could omit the RPM activated switch and make this a lot cheaper. The factory service manual (for the 1986 rx7) says the ACV relief solenoid opens at ~3600 rpm which is just a bit earlier than the 3800 RPM the 6ports are supposed to open. havent tried that though.