I think you'll find that the SD455 will 'tolerate' being over-cammed a little and still make TONS of power throughout the power band.
Definitely DO NOT run the 068 cam. Not with the SD heads.
Choke, choke, choke.
Our SD455 TA has the HO higher-lift version of the 041 cam in it. I don't recall the specs exactly. I think it achieves about .520 lift with 1.5 rocker arms.
Older-built,
well-worn engine with Tri-Y headers, full exhaust, 3.08 gears and T400 with stock convertor.
Daughter drove it to 13.95 @ 100.5 mph on Hoosier 10" slicks shifting at 4,500rpms (with the shifter in 'D").
Absolute tire-scorcher on the street.
When we rebuild the engine next time, we'll put in a bigger camshaft.
