The car was found and a forensic examination made, way before Jim Hanratty was even remotely in the frame for the A6 case.
I'm sure you know as well as I do that no-one (at least no-one whose identity/ies have come down to us) was in the frame until the cartridge-cases were found at The Vienna Hotel. Then of course Acott & Co were hot-foot after Alphon a.k.a. Durrant, and only when he was cleared did their attention turn to Ryan a.k.a. Hanratty per the Vienna's visiting-book (which, as an aside, he assiduously signed but could apparently not do likewise at Ingledene).
Any forensic evidence found in the Morris which could not be matched to known previous occupants of said vehicle would have been carefully noted, photographed and stored. The logical explanation is that Hanratty, either on his own or with assistance, gave the rear of the car (he was apparently never in the front) a thoroughly good cleaning somewhere between Deadman's Hill and Redbridge. However, if he had such foresight, why the hell didn't he dispose of the gun? I can think of one possible scenario........
Graham
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