problem with dual point no spark

It's not clear to me how you actually gapped the points. It is IMPORTANT that points gap be properly set. A dwell meter is the best way, a feeler gauge is less accurate. You must set the two separately. If you look carefully, one set is the "firing" set, that is, as the dist rotates, at some point both points are closed. As the dist rotates, one set opens, but the second is still closed. There is no spark. Then WHILE the first set is open, the second set opens so that BOTH are now open. THAT IS the point at which the spark is made.

I used to set them like this:

"Rough them in." Block the "firing" (last opening) set open, and set the other points for proper dwell. Then unblock that set and set the second set for "total" dwell, as I posted in the chart earlier.

You want them to "lean towards" more open to start with, as they wear towards closed. So block that one set, and set dwell about 28 (27--32). Then unblock the other set and set those with both points operating for about 38. (37--42) Be sure to put "a bit' of hi temp lube on the leading edge of the rubbing block. GOOD quality points used to come with it, and you used to be able to buy lube in little tubes

Anything is better than nothing, but don't use too much.

Always set timing AFTER you have made any points adjustments