[ercoupe-tech] Ercoupe Seat Belts?

[jwardercoupe]

I want to install a new seat belt system with shoulder restraints. Is there 
already an STC for the Ercoupe to do this?  And if not why not?  I figure that 
the FAA should have made this as easy as possible for us to make our planes 
safer than they are with the old lap belts.  I have a 415G model and want a 
4pt. system with the double Y-type of shoulder belts.  Do I have to submit a 
337 for this or can I just do it under a current STC?  Thanks so much - Jerry