Looking at a used (looks new) 8456 MSD distributor for sale. I'll put it to the test and see what i get. It's $70, looks cool and im a junkie. lol.
I assume the stock distributor is aluminum also? So the MSD should'nt heat soak the TFI module any worse than the stocker. Depends what the stock material is vs. i think the MSD is 6061. Maybe the MSD material soaks up more heat actually making it worse than stocker.