How much trouble am I in?

Yes, I'll crack the drain plug and see what comes out first, but I'm not expecting much water as I can't see that the level in the radiator has gone down any. I thought about that UV leak detector fluid for cooling systems- it should show in clear oil, right? Maybe that would be the least invasive first try. If it's positive, I'll pull a valve cover and have look and take pictures. Except for the filter adapter (aluminum one that came on the engine), the engine sealed really well and I hate to break into it before I have to. Meanwhile, think it would be okay to idle the engine until good and hot and check the oil again? You guys are making me feel better about minor condensation.

Heads were checked for cracks when the stock valve job was done. Looked okay.