I bought a “universal” MSD adjustable timing control add on box around 1998 that actually could only retard timing up to 20 degrees.
I toyed with the idea of mounting a slotted 1995 flexplate to the torsional damper with 20 - 30 degrees of advance figured into the mounting.
In the end I bought a 1995 Mopar Performance PCM for the 5.9 V8 Magnum V8 that advanced the timing 21 degrees above stock.

I still think a OEM flexplate,
or perhaps the right diameter cooking pan,
could be slotted to provide the crank signal and mounted up front.
Note the Chrysler Engineering double slot that tells the OEM PCM which cylinder numbers are which.

The MSD timing wheel does not have the right configuration, but could work with a Megasquirt EFI system.