hitnf,

I recently noticed that even though I replaced the coolant elbows a few years ago with the metal ones, mine were still leaking. When I removed the elbows, the rubber seals had clearly deteriorated. I replaced them and the leak is resolved. Check your elbow seals.

For the thermostat, I also used to get slow leaks out of mine. To seal it up I remove the housing and soaked up the coolant that was sitting inside the block right where I wanted to do the RTV. I soaked it up with a t-shirt until the level dropped a decent amount. With the RTV it has never leaked again. It is tough to separate the housing so do it right the first time - put a new thermostat and gasket in before rtving shut.

I have a 2008 gp base for reference. Good Luck.