I picked up a Lionel 6464 M & St L operating car this weekend, mainly because I have been looking for Minneapolis box cars, and I found an operating mechanism with a plunger inside.
the 3494 was one of the operating versions of the 6464. I don’t remember a M & St L version though. the shells were interchangable so it is probably owner modified.
Hello Kurt! Your 6464 is a modification alright. Sombody used a Frame & Mechanism from a #3484 Operating Boxcar & mounted a 6464 M & ST L Shell on it. Lionel never made any operating 6464s at all. Take Care.