I use the old MP electronic distributor with the tach drive. There are still some of them around...we may even have a couple around in boxes somewhere. I use a Moroso cable with an old SW mechanical tach from the old DC catalog. Been using it for forty some odd years.....there are a couple of old dual points with tach drives on Ebay now, pretty cheap, you could send it out someplace to be converted to electronic and rebushed...
https://www.ebay.com/itm/Mopar-426-Hemi-Race-Tach-Drive-Distributor-Prestolite/382311702025?hash=item59038d9e09:g:pEEAAOSwsFpaNRC4&vxp=mtr