[David Noble]

Cary, you should not make a request about a personal gun on someone else's thread.
You should have started a new thread, but being a new visitor to the site we'll give you a bit of leeway. Since you apparently own these guns, you know how they are currently outfitted and the condition. The only one I can help you on is the # 51358 grade 3 hammer 12 gauge. It is listed as a grade 3 damascus barreled top lever gun with a capped pistol grip and 30 inch barrels. The gun was made in 1887 and there are existing factory records to get a letter.
The Grade 3 28ga is not listed in the serialization and identification book. Depending on condition and configuration as well as remaining blue and case colors it could be a valuable gun. Unfortunately the PGCA does not show factory records available in their library for this serial number, however it was made in 1920.
I suggest you start a new tread in a day or two, after the site developer gets the photo posting mechanism working again, and post detailed pictures of the guns, a bit about how you came to own them, and of course any questions you may have.
And spend the $40 bucks to join the PGCA. It is well worth the money in knowledge you can gleam from the members here, as well as saving $60 on a PGCA letter confirming the way it left the factory, the date it was ordered and possibly who the original purchaser was, as well as any factory repair or refinishing that it may have received. The letters cost $100 for non members, but only $40 for PGCA members. On top of all that, you'll receive the quarterly Parker Pages magazine (at no extra cost) that each have hours of good reading and informative stories and pictures of Parker Bros guns by members of the PGCA!
Welcome to the forums!