Good morning,
Most emission places in Texas will hook up to your OBDII port under your dash
the machine looks at pre catalytic O2 sensor and then the Post catalytic O2 and see
if the Catalytic converter is doing it's job. if that fails then they check with a visual.
so unless it's totally hosed up, it should be fine. at that year the old header for the 7120 head, (same as mine) does not have a bung (Threaded hole) for the PRE-O2 sensor. that is an easy weld job to fix. JEGS.com has them for about 10 and the wiring should exist. if it is not throwing a check engine light it should be right.
Hope that helps, and by the by, the 7120 head is a lot more robust than the 0630... I got dirty pictures, the 0630 is a dirty little head. damnedest thing is it ran great... right up until it didn't.
Good morning to you all,