I had another chance to tour the TX room earlier this year in the top of Aucklands Skytower.
There is a previous thread here:
viewtopic.php?t=1185

I now have some better photos of all the heavy filtering
All the heavy filters coupled together lining the outside wall of the tower, this is near the start where the first transmitter is fed in, each filter takes a feed from one transmitter.
Towards the end of the train of filters, the pipes linking the filters and couplers get thicker.
The last filter connects into a series of meters where power and swr is measured

In my last post I said there were three different antenna systems, I was actually wrong. There are only two antenna systems, the first is the main 8 stack of circulars, the second is a 4 stack of dipoles.

Standard channel spacing is 800Khz, there are a few instances where some stations are spaced 400Khz apart. All the stations with 800Khz spacing are fed into the 8 stack, stations with 400Khz spacing (3 of them) are placed in between and fed into the 4 stack.
Separate group of filters multiplexing into the 4 stack of dipoles.

Very nice.

A baghead would have a field day with all that Copper in there.