Was looking around the local Pull-A-Part and found two 14 bolts, one is a srw under a mid 1990s van, the other is a drw under I think a mid 1980s van (not sure of the year). For use under a 1988 K5 which of these would be preferable, and what is the best way to tell a ff from a sf so I make sure the srw is in fact a ff? Thanks.

