Just FYI - - I've got some FAA airworthiness guys working with DER/DAR at EI to get the EI CGR-30P approved for skymasters. Eventually, EI wants the 337 on the AML for the CGR-30P combo STC. No word yet on completion dates for the project, but EI is working on it.
** July 2021 Edit: My FAA airworthiness guys are telling me that their position is "Non-STC'd engine instrumentation is not eligible for Field Approval, any any request would have to be forwarded to the Airworthiness Certification Office for Evaluation", per their
job aid . Specifically, Row D.13k or D.13t requires either a STC or an EVL (at the ACO). Bottom line for me: Until EI gets the CGR-30 added to the AML, it's a no-go. I'm now really thinking JPI-960.