I've replaced a couple on my TC. One from being not winterized enough. Any water left in there will freeze/expand and ruin the pump. Mine has slip connectors and a big rubber wrapped clamp that is screwed to the wall. I use a rubber bushing to reduce the noise from vibration.
It's not difficult to R&R.
As said, access is the woe unless you are young and skinny. Have all your tools and parts ready to go and use a big flashlight to see the connectors. It's kind of like plumbing under the sink except your working in a doll house!
jefe