I am going out on a limb here. I was the brake and front end tech at a Buick dealership in the 70's. Cars were routinely aligned as a maintenance, even when close to new and many aligned under warranty.
I realize I am talking 70's not 60's. But, every new Buick I aligned had ONLY the shims without "handles" from the factory. When performing the first alignment (whether at the delaer or an independent shop) MANY alignment techs would discard those in favor of the handled shims simply because they were a pain to keep in place with one hand while you were tightening the bolt with the other. The one exception would be the owner of an independent shop because he actually had to PAY for the new shims. Most techs didn't care about the additional cost, as they were paid the same regardless of whether they used new shims or re-used old ones.
This one is going to be hard to document either way. I can't tell you how many cars received an alignment during the warranty period. In fact the service advisors (who were paid based on the amount of work they wrote up) would advise the client to complain about a crooked steering wheel or "pulling" in the front end, just to get a free alignment under warranty.
So... unless you bought the car new, AND never had the front end aligned, it will be hard to know what came in there.
My PERSONAL belief is the non-handled shims. I have seen them as thick as 1/4 and as thin as 1/32 on factory cars.