Changed the starter with a ACDelco from Rock Auto and worked on finding oil leaks as I was getting quite a few drips just sitting in the garage in idle. After getting transmission leaks fixed it was much easier to just see the oil.
I bought some
Tracer Products Engine Oil dye and a
uvBeast 365nm MINI - Black Light UV Flashlight. Man, that made things easier!
1. The valve covers bolts were all loose, I could likely almost have been able to remove them by hand. Used a driver to hand tighten the bolts (not a ratchet). I've read these need to be checked after re-installing the covers with a cork gasket. I'd think the shop that replaced my valve seals would have not left them loose but they didn't say anything about checking the bolts after some time either.
2. On the old pan the larger bolts were loose, to me it just seems like my brother forgot to tighten them down when switching between oil bolt sizes. The dye clearly showed oil around the bolt heads - especially on the back by the starter.
So I went from quite a few drips of oil dripping just idling in place to no drips in a 30 minute idle test. Then after my test drive I dropped two dots of oil when I got back. Likely seeping coming around the oil pain at the main bearing area (at the peak of the curve it seems). I did tighten the diver side back oil pan bolt just a bit more too after all that too. The bolt head had some new oil on it (passenger side didn't). I don't think it is the main seal itself - there is no oil anywhere except for a straight down drip from the old pan. There is no oil on the torque converter/flex plate, it is dry as a bone.
I tested / drove without the cover as that darn cover hides the source, so that helped too.