2648 is the Mauser commercial serial number. The engraved number 5346 on the barrel seems to be Dickson’s. The stamped number 1760 on the triggerguard may be one of another retailer who bought in the rifle from Dickson & Son.

It’s very easy to convert a 98 or transitional Mauser barrel to takedown. On these actions the barrel is screwed in until it abuts a collar inside the receiver ring. To convert the tightly fitted barrel to a full screw-in takedown like on this rifle, screw it out by using a barrel vise and wrench. Rework he barrel threads a bit until the barrel screws in or out by hand. This can be done by either using a lathe or even by careful use of a triangular file in the threads. Bore and tap a hole into the receiver ring for a set screw to lock the barrel in.