1969 NHRA Nationals, 69 Buick wins D/S=9.00 what car/engine

[DeuceCoupe]

Well I am still slowly compiling NHRA history from 1971 back.
Just looking at 1969 Indy Nationals.


Says that William Robertson won D/S=9.00 in a 69 Buick.
12.24 at 109.69


Did the 69 Buick come with an optional 440-six-pack? (LOL)


Otherwise the lightest 69 Buick I see in the guide was the GS400 Coupe, 400/345hp Stage 1 with W/P=10.29 which would be in F/S=10.00 and not D/S=9.00


Did a 69 Buick really win this class?
Hard to believe the 400/345 Stage 1 would be factored to 390hp...