I just left my pump in place and unplugged it till I found a new one, I may have left it unplugged as it was not throwing a code.

 

I can say when I changed my plugs in the Camaro I have now for the first time the number 8 plug looked like it had never been changed. it is a major pain to get to and I am assuming whoever did work on it gave up trying to change it. use high quality plugs as you won't want to change them again for a long time. lol. first time ever changing them took me two days,,,, was changing plug wires too. swivel head ratchet and short spark plug socket come in handy. with my headers I have to take starter out to get to number 8

 

I pulled the relay, and mine didn't lit the service engine lamp either at first, but after some driving it came on, as it should I suppose ...

 

it will throw code if relay is missing, won't if you just unplug the pump. at least my 93 would not. different os then yours

 

Interesting, I will test to unplug it instead, in case it is the same on my 96, I wont have to drive arround with the service engine lamp on (which may include other codes as well if some new error occurs)

 

Yeah, I know about it being a real PITA, especially the #8 plug, and as you say, as it’s so hard to replace it, it may well never have been done.
My plan is to replace the driver’s side first in my own garage, and then take the car to my buddies garage that has a real workshop lift to work on the passenger’s side, probably still need to remove the starter though.
I got AC DELCO Rapidfire which is #2 on the 1-4 Ac Delco list, but I ordered them just after I bought the car, long before I knew about the hardship changing them

Do you remember how many of the plug boots that had the metal heat cover, I seen such on some of my plugs

 

Seems to be # 5, 7 & 8 that have the it

 

I left them off and used heat shields on the plug wire ends. also use heat shield on the starter. before headers I could get passenger side without removing starter. actually somehow got 8 from topside. I use ngk iridium. spend but good for lots of miles and dont seem to foul easily. had to switch to a hotter plug after engine build

 

I'm in the process of replacing plugs and wires, drivers side done and now working with the dreaded pass side, #4 done and #2 out.

The old plugs are the same ones that you have used (ngk iridium) and so far I haven't come across any plug looking bad but the one who installed them has used some kind of brownish looking gunk up at seat (not on the thread itself) that I'm trying to scrape off best I can before installing the new plugs, was thinking this might have reduced the cooling of the plugs a little as the heat is to transfer from the plug to the head partly via that surface.
I'm using AC Delco Platinum Rapidfire for replacement that I bought long before knowing about the hardship replacing them, but I don't drive that much so I think I'll be fine.

 

use antiseize on plug threads. always on aluminum heads.