MK67 diagonal suggestion (parks) ?

Hi. I have a Nexstar8 and have a MK67 on order. I want to be ready for it when it gets here, as I won't have a lot of time to mess around (Mars beckons).

I have a 2" diagonal (Parks Optical) and I assume you need a 2" diagonal due to how far back the MK67 throws its focus (or something like that anyway). Well, I have a parks 2" diagonal which is probably more reflective than my Celestron 1.25" diagonal. The n8 goes out of balance with the parks so it never gets used, but it MIGHT when the MK67 gets here.

Or am I wasting my time and I should really get a one piece machined diagonal or an Everbrite. Aparently the Parks is 90% reflective and I also have the 2-to-1.25" adapter allowing me to use all my Pentax XLs.

Is this a good combo? or do I need to quicky get a different diagonal (and/or eps) better matched to the scope.

For the record, I have:
2" Parks Diagonal
7, 10.5, 14mm Pentax XL EPs
11mm TV Plossl
30mm Celestron Ultima
and 9mm and 25mm Taiwanese Plossls (the 25 is pretty good)

Advice?
Tom.

My old (1996) MK67 has ample (maybe too much) back-focus. A binoviewer will come to focus straight-through while for single eyepices, I have to use a 2" diagonal (Intes) and a 2" extension to reach the sweet spot. Guess you won't know how yours is configured 'til it arrives but you might want to get a short extension if you don't have one already. I use 3mm, 4mm, 6mm Radians; 7-22mm Leica Zoom; and 30mm Widescan II all of which come to focus using the extension.

Good Luck, Tom