Stc To Replace Fact. Egt Guage W/jpi,uea, Etc.

Hello Everyone,

Looking for some help. i want to replaceb the factory EGT guage in my 73 P337 with a JPI EDM 760, or an ultimate engine analyzer US-8A. No room in panel for anothe guage, have new UPSAT stack plus second navcom, plus full co-pilot instruments. My avionics guy says JPI is not STC'd. Wondered if anyone knows of a field approval or STC for replacement of the EGT guage. Hope someone can help, Thanks in advance. Email me @ savagepilot1@netzero.com, or call me at 716-937-6527 days.