Sounds good to me. I'm going to try to register it and see what the DMV says. Thanks guys.
FWIW, just a little bit of advice if you care to listen. I would go in there with a positive attitude. Present any necessary paperwork in a polite, yet authoritative manner, with an attitude of complete confidence. Say NO MORE than is absolutely necessary, although remain cordial and polite. ABSOLUTELY, under NO CIRCUMSTANCES, do you volunteer or mention anything about this serial number being an oddball, or anything to warrant exceptional scrutiny. IF (and it is entirely possible) the subject comes-up from the 'friendly and efficient DMV person' that the serial number on your frame either does not match acceptable '41 Ford numbers (they have lists now-a-days just like we do), with a confident face and manner, authoritatively mention that this car came equipped with the Ford-approved, optional Mercury engine.
Just so that YOU understand the Ford/Mercury engine production process, as I said before....when Ford assembled a new engine back then, it was mated to a transmission which was common to both Fords and Mercurys...SAME transmission! At that time, a serial number from an allotted sequence was stamped on that top, blank pad on the transmission's clutch housing....
see picture below! If it was the 90 HP Ford engine, the transmission was stamped with a "Ford" serial number. If it was a 95 HP Mercury engine, the trans pad was stamped with a "Mercury" serial number.
These engine/trans assemblies usually went into short-term stockpiles awaiting shipment to an automobile assembly plant. After arrival at assembly plant and installation into a chassis, that number stamped into the trans pad was hand-stamped into the passenger car chassis in three locations on the driver side frame rail, becoming the car's official serial number. The stock Ford engine in '41 was 221 cu. in. and was rated at 90 HP. The "OPTIONAL" Mercury engine was 239 cu. in. and was rated at 95 HP. The important info here is that cars were initially "serial-numbered" by the serial number originally stamped into the trans pad. Mercs had their own dedicated numbering sequence. Have this info fully-understood in your head so that you can rattle it off to the DMV clerk with authority! Good luck, and report back!
IF your car happens to have the original transmission in it (with that "99A-" serial number stamped into it), I would take a picture of that with you to help back-up your documentation. DD
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