As we began the restoration of Michael Argetsinger's 1973 Elden Mk10B (s/n 140/1) last Sept, we had to graft a few pieces of another Mk10 chassis to make one solid, straight, complete car.
The donor chassis that was used to fix much of 140/1 was AM73-49, a car that had run in SCCA Autocross competition since 1996, and before that was a solid runner in Alberta on the club racing circuit.
At some point, both chassis had Elden Falconer bodywork on them, which was a rarity in itself. Mike actually imported 140/1 into the United States with Falconer body on it in hopes that the upgrade would help it sell. Second owner Randy Dounce confirmed having white Falconer bodywork on the car in 1974, having purchased the car early that winter from Michael.
So as we are making one complete chassis using some of AM73-49's DNA, and since Mike's chassis did not have an Arch Motors #, instead the oddball 140/1, both numbers will be stamped into the rear bulkhead to designate the merging of both chassis lineages with this build.
Because numbers mean everything.