Anyone knowledgeable about
old ( +20 years perhaps)
vented
“Real Fyre 24”
natural gas fireplace inserts ?

This is a simple match lit unit.
Has four rectangular refractory cement bars surrounding the black pipe gas burner.

I am looking for an installation manual,
or pictures of the insert installed.

I know about the webpage of today’s Real Fyre:

https://www.realfyrestore.com/real-fyre-fuel-injector-natural.html

my old unit has a fuel injector that looks like that,

and an “Air shutter nut” that screws onto the fuel inctor
.