I have a 12 gauge Remington 1889 I inherited and it has a few flaws, small ding in the barrel at about 23", my great uncle used a cheap engraver to put his social security number on the bottom of the receiver, and the usual wear and tear.  I'm thinking about having the barrels cut to 20", rechambered for 2 3/4" shells, and a new front bead installed.  Any thoughts about this?  Keep it as is?  Anyone know anyone near St. Louis that can do this?

Leave it original or do a restoration. Any modifications will further decrease its value. If you want something to shoot buy something new unless you want to reload for it.

Does it have “twist steel” barrels? If so, probably not advisable to shoot modern (smokeless) shotshells through it.

Shame about the poorly engraved SS#. It was a thing for a while. When I was a little kid, I remember watching my dad engraving his SS# inside the cabinet of our TV. I asked him why and he said so he could prove it was his if it were ever stolen. I then asked why he didn’t just use his name instead? He thought about that for a minute then told me to go outside and play.

Now we’re told to guard our SS# like it were nuclear launch codes.

Anyway, me personally, I would give it a good cleaning and keep it for now as an heirloom. Do more research on the gun. Later you can decide to go forward with a restoration or alteration if you like.

Nope not Damascus barrels.  I have a lot of collectible firearms and I think this is a good candidate to turn into a coach gun.

Those are nicely made. I would cut it to 20" in a heartbeat. Be sure and replicate the solder between the barrels and rib at the muzzle.