Im betting this subject has been reviewed before but i didnt own an OLDs then so forgive me.

Installing a VINTAGE AIR and uncovered some yellow ink stampings on the firewall.
KKK
B
II
What do they mean?

 

When an inspector completed a task, they stamped the firewall with their mark.

I didn't realize I had any until I removed the sealant that was sprayed over the firewall.

 

Stamps are usually inspectors, like said, or part callouts. Grease pencil is usually handwritten flags to watch for a low runner, like you'll see W-29 sometimes for "hey, this is a 442," and sometimes it's just a mark by the line guy to say he did something.

Funny story, they use grease pencils at my factory to help the team member to remember to do something, since you DO it, pick up the grease pencil, and mark it, and put it down. Well, we're hiring anyone and everyone, so they wanted me to put an electronic Pokayoke Interface (PI) box on it,
so that the pencil was sitting on prox switch that would stop the line unless you picked the pencil up to use it once per car going by. I said something to the tune of "I am not pokayoking a ******* grease pencil mark which is there to remind the TM to do their job anyway. You want me to PI the
part picking itself, sure, but the pencil mark is irrelevant to the car and it ain't happening." We ended up using a pick light, which is something that your hand triggers as you stick it in the tote for the part on the flowrack.