I measured across the UCA's from flange to flange (not bushing to bushing). You can see the measurement in the pictures as far as where I measured from, I turned them over as that was by far the easiest, most consistent measurement. Probably not the greatest measurement to translate to a tubular UCA though. You can also see how the arms look pretty different from one to the other as well.
A-body: 8.5"
E-body (all)/B-body (62-72): 10.5"
C-body (taken from a '73, not sure how else that lines up) : 11"