Info is sparse with the FAA.
STC Number: SA793CE
Description of the Type Design Change:
Installation of Lycoming O-360-( ) engine and Hartzell HC-C2YK-1B/7666A-2 or Sensenich 76EM8S5 or McCauley 1A170EFA propeller.
The proper ways to get the info would be to contact the STC holder directly.
This certificate issued to:
Williams Robert or Barbara
213 N. Clark, Udall KS 67146
Phone: 620-782-3317
Since these folks may be "gone", then you'd need to file an FOI request with the FAA
Responsible Office:
ACE-115W Wichita Aircraft Certification Office Tel: (316) 946-4100
A similar STC, SA805NE, was issued by ANE-170 New York Aircraft Certification Office Tel: (516) 228-7300.
Either one of those requests will need a certified, return receipt showing you failed to contact the owner of the STC.
A little more details may be had from this starting point:
http://www.faa.gov/aircraft/air_cert/design_approvals/stc/stc_install/
Other References:
http://www.piperforum.com/viewtopic.php?f=2&t=1520
http://www.pilotsofamerica.com/forum/showthread.php?t=42675
http://rgl.faa.gov/Regulatory_and_G...2EB42D3EC6D0C15185256CC20058E4E5?OpenDocument
http://www.pilotsofamerica.com/forum/showthread.php?t=46050
Also, you might check the registration database for other PA28-140s with O-360 engines and see if the owners could take a picture of the placard. This would assume you had been issued the STC directly, and it was properly logged in your plane's logs and AFM (and ideally filed with the FAA).
Just to be sure, know that if you're trying to upgrade, the STC has to be issued to your specific aircraft by the STC owner. Can't just be a copy of the instructions, copy of the placards, and a signoff that it's mechanically sound.
