Coolant leaking behind the exhaust manifold to the left of the thermostat?

Have you had any chance to shoot a video or take some pictures? The location you refer to has a few lines there that can leak. Seeing the location would help.

You mean #6 in the image? That has O-rings on the end, but if it's leaking in the middle, it possibly rusted through. Replacement is basically drain the coolant, remove the water pump housing itself and then you can get to the pipe. Remove it, be sure the seals are on the new one and reverse the process.

Did you remove only the pump or the pump housing that bolts to the block? The pump should only have 4 bolts (item 2) and comes out the front of the housing. In your case you will need to remove item 4 from the side of the engine. Then you can remove the pipe, check/replace the seals and re-install it with the pipe ends fully seated. It's a tight fit but can be done with the manifold on. Pull the alternator and you should be able to get to the 4 bolts.

The tube could be rusted through causing a leak or misalignment. Either way you need to remove the coolant tube to inspect or reinstall. Please use the image Steve has featured above.

Hmm, in that location I'm not sure how it would get bent unless someone had it off before and installed it wrong. However, you found it and are fixing it. Be sure to install the new one the correct direction. The bent end goes on the water pump end.

In use it should only fit with the formed end facing the pump. I've seen them bend from rust and if they were installed wrong. They are sort of protected in there. But the new one should solve that. I would take some time and clean out any crud from the seating areas and use a light film of silicone lube on the rings just so they slid into place without rolling. Don't use regular oil or grease as that will damage the seals.

That's got a bit of a curve. The new one should seal it a bit better.

You are welcome. Hope the test drive goes well.

Don't owe me a thing. Take the family and friends out someplace fancy. Or with current prices, buy some hot dogs and burgers and throw an "I fixed it" party.