What the two woofers "play" in the C60(since it is MTM) is irrelevant.
The relation the tweeter has to the woofers is the problem.
Removing it from the cabinet and moving it up, either...
1. By re-mounting to the top.
2. At the TV pedestal.
Makes no difference.
However, the closer the tweeter gets to the screen...The better.
The two woofers are relevant. That is the whole issue I am trying to avoid. Right now I have my C60 vertical and it is carefully angled so that the tweeter is aimed right at the seated listeners ears, therefore, the seated listener is effectively sitting "on centre" to the centre channel no matter where they sit across the seating area. I could keep the centre pointed the way it is, and raise the tweeter above them, but the interaction between the crossover between the tweeter and the two mid-woofers would begin to cause more problems. The tweeter would be closer to one woofer than the other, and the tweeter and woofer play similar freq around the crossover, and that would result in problems.
What I was proposing, is to take the tweeter and port in the C60 and swap them, AND to remove the midrange frequencies from the lower woofer. This could be done by simply replacing the C60 crossover with a T55 crossover, because the driver arrangement is precisely the same as what my altered C60 would look like. You have to look at the speakers and picture what I'm saying.
The best option would be to take a T65 and take out the middle woofer section. The cut made to the speaker would be completely straight, and you would then use various means to put the speaker back together. Again, you'd have to use a T55 crossover or make the T65 crossover the same as that of the T55. Another option would be to take a T55 and shorten it to approximately the size of the C60. This could be messy because you're just putting a bottom on the speaker, but it could work.
For now I think I will try a B25 and see how the sound is. In fact, I could go to 5.1 and try one of my B15.
The whole idea I am trying to achieve, is to make a centre channel the height of my current C60 centre channel, BUT, with the tweeter at the top so it is closer to the TV and closer to the plane of the tweeters on the towers, and lastly, to avoid the MTM design altogether, as I find in my reading, that the MTM design has un-even frequency response even dead centre.
Look at the T55 and look at the C60. I want a C60 cabinet with the facia and drivers of the T55. That's it.