Okay, so I get this right, I whack a Big Barlow (2x) into the 2" focuser, then the Parcorr with whatever eyepiece, and set it to a particular mark determined prior (I read the post on working out the positions and marking the Parcorr for each eyepiece).
I'm guessing the Parcorr is 2" in and out, with the removable 1.25" adapter. So it can handle the 36mm also. Correct?
That's a truck axle setup!

I may need to bolt a 12volt car battery next to the fan.
BTW, wont that become F5.5 or thereabouts?
Thanks for your help.