I will give the points a cleaning and recheck the resistance measurements.
Thanks Mark

Tried to clean points today-the maximum points opening seemed very small[don't have a feeler gauge]but compared to .025 of plug gap it seemed less than .012.Very hard to slide a strip of 150 grit sand paper in this narrow gap [what tricks do people use to keep the gap open enough to slide sand paper in-I tried using a small screw driver below point contacts :but very difficult to keep points open with one hand on screw driver and slide paper into gap .with other hand holding a small sand paper strip that I cut to fit between this narrow points gap.I was only able to slide the paper out across the closed points only about 2 times.I no longer had spark after doing this.Perhaps I have sand/grit causing the new lack of spark .Will get contact cleaner and try again to clean point surfaces.Any hints to do this easier.Any thoughts about spark loss ?

I just used to use stiff emery but a reasonably fine grade & doesn't bend too easily under pressure. But not done that for years. Not sure what bike you have but could pull the flywheel if you have a puller to make easier to get at. Something i've never thought of till now, you could adjust the gap quite wide at full lift to take the pressure off the sand paper but still get it scratching some. Whatever bike, you need about 15 thou max anyway, or a bit more than 12 to get timing in the ball park.

You shouldn't need contact cleaner, although it wont hurt.
Slide a strip of plain business card between the contacts after you've cleaned them with fine wet and dry/sandpaper, I use 800 grit.
Worth investing in a set of feeler gauges too.