Thanks for the info and for Bill's clear photo.. If there is no GM (USA and/or Canada) documentation, yet the frme ID was put on all vehicles at the factories, and the existence of a frame ID was not publicized for secrecy purposes (as if thieves would not quickly figure this out), it should be in (or near) the same place on all 55-2nd and later (let's say 55-59) Chevy truck frames?

What is the location?

Would people with 55-59 Task Force trucks please check that location and post the year and model of their truck and the code they found on the frame? Posting a photo of the ID would be bonus information.

This will move this recurring topic/speculation from anecdotes to a pattern?

There is no reason to doubt the use of frame IDs, and there is no doubt that some trucks have frame IDs (they have also been reported on 47-54 trucks, when no IDs were put on the frames of trucks I have owned). However, if a high % of 55-59 trucks have frame IDs, even this Doubting Thomas will no longer say "show me".

What is the location of the frame ID?
Passenger or Driver side of frame?
Bottom or top or inside/outside of the frame rail?
Can it be readily found/photograped, once you know where it is located?

Please post a description of the location that would allow 55-59 owners to easily check their trucks.