there are 3 exhaust styles for the s-series:
'91-'98 (maybe some very early 99) DOHC: 5-bolt
'99-'02 DOHC: 9-bolt
'91-'02 SOHC: 8-bolt
so yes, a header (singular when it's one assembly - V6 engines have header
s because there are 2 banks of exhaust, thus 2 assemblies) for a '96 DOHC will fit a '98 DOHC.
