Modifying PSB Image crossover possible?

I want to take my PSB C60 and essentially turn it into a "short" T55. I am already using it vertically, but I want to rearrange it to make it a short T55. There are two things I need to do. I need to alter the crossover so that the midrange from 500 Hz and higher does not come out of the bottom woofer, and also, I need to figure out if it is ok to have my centre speaker as 6 ohms instead of 8 ohms.

Should I just get a T55 crossover or can I look at the T55 crossover and the C60 crossover and somehow make the C60 crossover like the T55 by adding what is missing and/or changing it?

The PSB C60 is a horizontal centre speaker with M T M and the T55 is a vertical tower that is T M M from top to bottom. The T55 is approx 6 ohms and the C60 is approx 8 ohms.
Anybody have any ideas? Do I need to replace the crossover in my C60 with a T55 crossover, or can I alter the C60 crossover so that it is the same as a T55?

I may even do this modification without changing the driver orientation of the C60. This will eliminate much of the lobbing issues with the MTM design, and yet keep the power handling and sensitivity higher than a bookshelf.