Exactly.
There is one company that at least used to make a 130T flywheel with the notches but I have yet see anyone ever do it. I saw one post about someone buying it, and then later selling it. And the one guy that has done it took a 143T flywheel and turned it down to fir the 130T ring gear. He is the only one I know of to use the Magnum EFI on a 4 speed.
I built crank pulley setup that I hoped would duplicate the signal since my LA couldn't run the above flywheel without a bunch of work. But I've changed directions so who knows if it would actually have even worked.
Edit - I forgot about the guy on YT that sandwiched the flywheel. So I guess there I 2 guys that have done it. That guy completely slipped my mind.
