Received the side vents today that I bought off
@Snydersmuncher93 in perfect condition. Had a look at the passenger side one in the car and had a real piece of luck when it simply came out just pulling with my fingers! Two metal clips still attached, both on the other side from the one still attached to the replacement. Removed these and Superglued them on to the replacement, slotted it in, job done that side!
Then having nearly pulled the worn fasica right off the worn headlight knob without it even budging, I went and read up on how to actually get the headlight switch out, so simple! Unfortunately with it out there's not really any access to the lower clips of the driver's side vent that I was hoping for. I think that one will end up getting its missing slider via a vane transplant. But I put the replacement headlight switch in while I was there.