[caddycruiser]

Correct. Brougham was a fancier trim package, as far as seats, etc., and limo converters are focused on largely "fleet" level vehicles--rather than chop and extend the most decked out versions possible, they focus on specific base'ish models with the desired suspension, cooling, etc. upgrades. Another reason why just because a lot of these cars see a LOT of HD driving and wear, and the most focus is on back seat passenger features, so it isn't a biggie that the chauffeur has heat or memory in his seats.

Same way that you would see new Performance or Lux III edition DTS's or Town Car Cartier's (or whatever the current top trim is) made into livery vehicles.