Manual steering isn't a factor.
The correct A.I.R. fan belt measures 3/8" wide X 47-1/2" long and was coded YE in box #37 of the buildsheet.
The original 1969 Chevrolet Chevelle/Elco L-78 part number is 3921934.
http://www.gastanks.com/1969-Chevell...nfo/29-B-589B/
The original 1970 Chevrolet Chevelle/Elco L-78 part number is 3883248.
http://www.gastanks.com/1970-Chevell...info/29-B-603/
Quanta is very good,but can be a lil confusing @ times.
I recommend calling them first & asking the actual part# stamped into the belt & dimensions of the belt you want before ordering.