Determining VIN or Serial number on 1968 Travel Queen Camper

Not sure when the current "standard" for VIN numbers went into effect, but back in the 60's and 70's IIRC some mfg used a VIN number, others just used a serial number. SN may have been More common on campers than trailers.

I think the same thing applies to VIN number location.

I had a cargo trailer built in the late 70's early 80's and it didn't have a VIN number just a mfg serial number. But I didn't have trouble registering it and getting a plate for it.