My question is... does a CDI ignition require a bit less advancement (simply regarding the position of the mag plate) than it would with the old points type?

The reason I ask, is that a while back I took an old 6NHR hotrod and put on a OMC ignition (like the American HRs used). All I had to do was to shim one side of the flywheel key slot, reshape the key, and use a thinner "wave spring" washer to give the nut full thread. It worked out perfect. The way I timed it was to set the old Phelon breaker at .018, detect where it breaks, then set my home made piston stop at that precise point. After switching the ignition system over with the OMC wheel, I put in the piston stop, then I made a mark on the block and a equal mark on the wheel at the stop point. I then used a timing light to get the marks aligned via the strobe indicator while spinning it over. Well, when I went to try it out, the darn thing kicked back and nearly snatched my fingers out of joint. I then retarded the mag about 7-degrees, and that problem was solved. It ran like a dream. I just wonder if it is really at the right point as now, compared to the old like this? BTW, I found a surplus HR16B Tilly pumper carb, rebuilt it, and put it on my hotrod and it is great!! All I had to do was to open the carb side of the original carter adaptor to match the tilly as it is about 1/16" larger. I have the diaphragm side facing downward and rigged it with the throttle cable coming in on the front. It actually works well like this and doesn't get in the way, looks good to.