I've had this thing apart and back together a lot. I think I've probably gone through 5 headgaskets at this point, and I've only had weird failures like this on 2 of them. So the odds are... pretty good?
Anyhow, I cleaned up the head and block last night, put a little copper spray on the HG (so far I've gone back and forth on that, sometimes some Hylomar, sometimes some copper spray, never have done it totally dry though).
Right before I set the head down I thought I'd run in a couple of the short head studs to act as a guide for the head, so it goes down onto the block/HG straight and you don't have to scoot it around. Put the first in, screwed it in. Then, I wasn't paying enough attention (my kid was out reciting an endless spiel of Portal 2 facts/quotes) and when I went to put in the second stud, instead of the head bolt hole I put it in the oil drain. And it fell inside. All the way inside. Clink, clink, rattle, clatter. Hit the oil pan.
Oh, boy, that was a stream of obscenities. 1 half second of inattention, now I'm going to have to pull the motor out and fetch that damn thing out of the oil pan. I pondered briefly just leaving it down there, and using a stock head bolt. Nah.... not going to do that.
Then, just for S&G's, I decided to try a little fishing. I got one of those long flexible claw tools (
https://www.amazon.com/Flex-Cable-4-Finger-Retriever-Pro-Tools/dp/B006ZEOXJY ) and stuck a powerful little hard drive (neodynium?) magnet on it. I tried the hole I'd dropped the stud down, nothing down there. Tried the hole next to it. Nothing. Tried the next one down and... was that a piece of loose metal? It was! But not a good grip. I gently pulled it up and as I did, I started to feel the magnet sliding over threads, click click click. Very gently, kept pulling up. I could feel when the magnet finally done sliding up the length and around to the end. And then I had to pull it up out of about 8 or 9 inches of block. Which isn't smooth internally, every few inches it would catch, and I had to gently twist and wiggle, thinking the stud was going to drop of at any moment. Until, finally, the stud appeared at the top of the hole and I grabbed it.
I have no idea what the odds were on that working. It's a tiny hole, barely bigger than the stud itself. And there are only a few of them, and the flexible grabber can really only reach straight down from them, so the odds of the stud being right under one were low.
That was a HUGE relief, don't have to pull the motor, I can just proceed with putting the head back on.
I set it on, torqued to 30 ft lbs, torqued to 60 ft lbs, let it sit for the night. This evening I'll go up to 100 ft lbs in 2 increments. Last time I did 90 ft lbs, and suspect that just wasn't enough.