GM has license to use the Trail Boss name, but I couldn't find reference to any vehicles produced with that option until 2016, starting with the Colorado pickup. I found a few Trail Boss Suburbans online and they all had similar pedigrees, namely, late 80's 1/2 tons located in the Pacific Northwest. This has me thinking that there was a dealer in the Washington State area doing these as a dealer-installed option, using a third-party vendor to do an interior makeover and custom exterior paint similar to the van conversions that were so popular back then. The running boards were different than the standard DeeZee boards that most Suburbans came with, and the roof racks were shorter in length but taller than oem racks. This all tells me there were probably late 80's vans running around Washington with similar equipment, installed by the same vendor.
Here's a couple pics I found. This first one screams van conversion.
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Only a couple of exterior pics of this white one, but the burned-through paint looks familiar. It's like this one and Thesiger's were painted by the same guy.
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Here's an interesting one. An '87 from Washington (again) that isn't a Trail Boss, but has similar aftermarket features. Maybe this was an earlier version that gave the dealer an idea to create the Trail Boss option. A lot of similarities in the woodwork on this one to the black one above.
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