The horn relay I believe is on the backside of the strut tower next to the headlight relay. The one on the front side might be your parking lights? Turn them on and unplug a spade one at a time. I just messed with these the other day. I can't believe I already forgot. The one near the fan shroud is for the dual point setup I think?
Although yours looks different from what I recall. Maybe they replaced the old one with a newer style.....
Yeah , this^^^^^^
I think my cousin used to use zolatone inside of beds and such.
Now that I think about it. I have a friend who did his whole dash. Something different I guess.
Remember when tweed was in?
I don't know if you absolutely need the spacer. I have never tried installing without it.
Techno toy tuning carries them. You can also find them on fleabay. I bought mine used from another 510 owner. I had to buy the longer bolts separate.