I have Heinze coils for my 1911 that RV Anderson rebuilt and they are beautiful.
However, as cited above, the points get out of adjustment, which is why some many owners back in the day used master vibrators.
I like driving a lot and like things to be as original as possible, so I needed to figure out what I was going to do to have a consistently good running car.
I looked an the reproduction Heinze coilboxes that fit 1914-1927 KW coils, but was not overly enthusiastic.
So I rebuilt a set of KW type coils and rebuilt the boxes to fit into the original Heinze coilbox.
I had to modify the contacts on each coil so they have secure connection in the Heinze coilbox.
Here are some pics of what I did:
The front to back dimension had to be reduced by about 1/4" so I ended up removing the glass insulator so the new capacitor would fit.
With a couple of side to side shims they fit into the Heinze coilbox perfectly.
And if I want to, I can slide them out and put the original coils in place.
: ^ )