J&S used with MegaSquirt??
 

So I'm about to Squirt my Miata which will become a turbo car later on this year....

Is it possible to "hack" the old J&S safeguard to work with the MS as its knock sensor?

Has anyone thought to do this yet?

No, because there's no reason to. Do a search on KnocksenseMS. Fully programmable knock sensor for use with the MS for under $100. Sell your J&S.