To say the Orioles were erratic in their choice of number fonts during the 70s and into the early 80s is to be somewhat generous...but, IIRC--and again, I'm much better 1989 forward than backward--when the Orioles used full block numbers like the ones shown on this jersey, I believe the rear numbers should be 6" and the name should be black only. Full block numbers and two-color NOB should be restricted to road jerseys during this period.
Once again, the combination of Lou! Lampson! and an Orioles! jersey! results in a major! train! wreck! with! lots! of! fatalities! (Why does he write LOAs like Shatner reads lines?)