even Chrysler was inconsistent

B029M (B-zero-two-nine-M) yes, I see the second digit is a typed "O" = Super Stock Barracuda with M = special order V8 (cross-rammed HEMI)
8B = 1968 - Hamtramck, MI assembly plant
299147 = VIN sequence

there were NO letter "O" or "I" in VIN numbers until the '80s

H6X = black bucket seat interior
999 = special order paint - NONE
T3 = transmission 393 - 4-speed manual
SA = standard rear axle (on a 4-speed SS Barracuda - it would've been a b-body DANA)
218 = SCHEDULED Production Date: Sunday, February 18, 1968
***** the UAW wasn't working Sundays in 1968!