Finally got to the bottom of my crank but no start condition. The cam sprocket came loose, maybe I didn't get a torque wrench on it, although it ran for 10 years before the trouble started. So it looks like the timing chain slipped a little past 180. I figured it out because at top dead center on the crank, the #1 cylinder was in valve overlap- the intake not yet open. Got it running, but there was a rattle from the timing cover. Once I removed the timing cover I found the loose cam sprocket.
My cam card is long gone, but I degreed the cam initially with timing wheel and runout gauge and the cam looked good. The thing that has me scratching my head is that now when I line up the dots on the timing sprockets at their nearest, I'm back to valve overlap, 180 from where the spark should come in. I can't explain it unless the cam sprocket dot is meant to be opposite the crank sprocket dot and not adjacent. My 60 year-old brain can't remember how the dots looked the first time, since I was depending on the degree wheel more than the dot line-up. Any thoughts on the matter, or do I line it up the way I think it will work?

When you line up the dots on a timing set you are on #6 firing which is 180° from #1 firing. It's just how the sprockets are marked. It matters not one bit because this is the correct relationship between cam and crank. Just drop the distributor in to fire #6.

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Joshua

OK, that's great to know! I was just coming back to mention that I was trying to line things up with the distributor set to fire on #1, which you correctly assumed I meant. Thank you.