you used to be able to buy?

When I was running the duraspark distributor you could buy a spring kit to adjust your curve.I have even removed the lead spring and ran one spring.This would give the advance quick and still give enough tension to keep timing in place.I read some articles on filters and they really bragged up the fomoco filters?Especially the old 7.3 diesel filter but If I recall its 5" tall so wont work for you. You were talking about 2v heads and I think T Meyer uses the Aussie 2v on his circle trackers. ?