Dumb square body questions

[Hulk Will Smash]

OK, I've got a couple and I haven't had any luck with the search function (oh the 58 second blocks of time I've waited to peform another search... )

Anyhow, for now, two dumb questions (but anyone else is free to jump into the "I should probably know that pool" with me).

I have an '87 R30 crew cab dually with a 454 and TH400:

1. My SES light is nonfunctional. I was going to attempted to replace the bulb, but it occurred to me that I have no idea which side of the cluster (speed-o or gas gauge side) the SES light is on. Which gauge is it in and on which side (left or right)?

2. Will the back seat brackets from any squarebody year mount up to my '87's mounting points or did they change the brackets at some point?

Thanks!