There is a 25% chance that my grandfather is in one of these two rigs. He was a TDC guard in 1974 stationed in Sugar Land Texas. He drove one of their ambulances to Huntsville for this hostage situation (which ended badly by the way). The photo said four ambulances responded and to the best of my knowledge they were all TDC rigs. Here is a link to the photo which is on Ebay now.
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