Anson & Deeley has nothing to do with the bolting, it has to do with the lock mechanism. The Remington Hammerless Double Barrel Shotgun was actually built on two U.S. Patents. No. 528,507 granted to Rimmon C. Fey on October 30,
1894, which really concerned the manufacture of the frame to essentially house the Anson & Deeley locks. The other was No. 528,508 granted to Rimmon C. Fey and George E. Humphreys, also on October 30,
1894, which covered the ejector mechanism.
The bolting on a lip of the rib extension by a rim of the toplever is essentially a "third" fastener on all the Remington Hammerless Double Barrel Shotguns. Depending on grade, time frame or luck of the draw, Remington Hammerless Double Barrel Shotguns can be found with typical Purdey double underbolts, a single lug with a single underbolt, or most commonly the triple underbolt.
Remington barrel lugs for single, double, and triple bolt.
I've got no information on the serial numbers of the guns William Heer used.