John Kleber wrote: …  3.  Is there another engine monitor system (perhaps the JPI EDM 900) that will drop into my present panel cutout for the VM1000?

John,

Not sure how close it is to a “drop in” but look at the Electronics International MVP-50 monitoring system if you elect to abandon your VM system. I’ve not yet flown with my MVP-50, but the capabilities are most impressive, and the installation/set up very straightforward. I am using it to monitor a number of systems/functions on my IV-P, in addition to the standard engine things.

Bob P