Mr. Kaas is right on the money- Del Grego the parts and knowledge, and the Parker ejectors require a watchmaker's precision touch- ditto the Alan Lard LC Smith single trigger- No place for an amatuer.
I wondered about the entire serial number of a fine double on any website or discussion forum- there are "trollers" after Walleyes, and "trollers" after confidential information with an eye to possible "no good deed"-- I feel safe in posting here on the PGCA: the GHE project Parker- with VH No. 2 barrels and a later series GH buttstock- so three sets of numbers- Austin Hogan was kind enough to print that story a few issues ago- I also posted the sn of a PH 16 on the O frame (about the same vintage as the GHE 12 bore- 1905-1908 herein- without concern.
HOW-SOME-EVER-- I would NOT do that elsewhere. Perhaps the safest way for you to proceed is to send in a research letter and your check to our Committee- safe as houses, if the records are available for your Parker you'll have your answer(s), and if not, you'll receive your check back uncashed an a letter of explanation- Win-Win all the way--