Denny,
I wonder if undercoating was dealer applied and not factory applied. I know back in the day, many vehicles were special ordered and could really throw a monkey wrench in the history of these old truck, but of the last two 54s I have had; one is undercoated and one was not. I have had many TF half and 3/4 ton trucks and not a one of them was undercoated.
I think for originality either way will do. Although many items were not painted; if I were restoring for points, I would paint everything. Even if the paint looked like bare metal. But I am not a purest and want to drive my truck, so I will paint as I like. For me that means, I will paint and finish as if it were customized in the 1950s. Even if some of the parts are not from the 50s; my hope is that it feels like a 50s mild custom.
