Since you found the sticker with the serial number... The field under MFG# is the model number. E.g. B59516.711J0 is a 15k Brisk Air II.
If you found the serial number elsewhere, the sticker is inside. Remove the intake vent. The sticker is sort of buried but visible from there.
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TT: 2018 Surveyor 243RBS TV:2019 F-250 XLT 6.2L 4x4 Crew Cab