1. There is no replacement for having a decent tech-book with you while doing a job like this, even a Haynes or Chiltons is worth-while (I have both). They usually have pictures or diagrams that help too. Even AutoZone has tech info with specifications and usually pictures or drawings online to help. But an abbreviated procedure goes like this:
(You should already have the rear brakes adjusted by this point. If you haven't done anything with them recently and they otherwise work alright, you should be fine.)
A)Set the hand-brake up ten clicks, and release. Do this ten times.
B).Check both rear wheels, making sure they turn properly (so lift the back of the car, use jack-stands, and keep both wheels off the ground).
C)Set the brake handle up four clicks.
D)locate the little oval plug in the back (inside) of the backing-plate on each rear wheel. A 1/8" drill-bit should fit between the shoe and the park-brake lever (inside the brake drum), but a 1/4" drill bit should not.
E)Adjust the cable by turning the adjusting nut at the equalizer, between the two rear wheels, until the proper gap is set.
F)Release the lever, and make sure both rear wheels turn freely.
That is Chilton's answer, +/-...
For me, I say lift the rear of the car, set the parking-brake handle four or five clicks, and tighten the adjusting-nut on the equalizer until the brakes on
both rear wheels just start to drag. Fully apply and release and reset to four or five clicks several times during this process to help actuate both rear brakes evenly if you experience any difficulties. Release the brake and make sure both wheels turn freely.
Good luck...
2. IF "Car Parts Depot" has anything to do with "Depot", they are a bargain-level replacement part. I rebuilt the front-end of my '92 Grand Am with Depot lights, and they were good quality (even included Sylvania bulbs), and mostly fit right and several years later
still haven't fogged-over. BUT, one of the two corner marker-lights were assembled crookedly, and the plastic itself is more brittle than OE. For the price, they are hard to beat...
3.

Sorry, can't help much there... Cavalier? Grand Am? I have a really nice set of blue ones from an Olds Aurora for my '90 'T-Type' turbo 'Retta, with the slide-out extension and the fixed plastic front visor that lets you have a visor to the side
and front at the same time

, but they are a little too long considering the overhead console in that car, and the angle from the mounting-plate is totally wrong, so I will have to redrill the holes for them, which I really don't want to do. They are also massively thick, considering that both sides have lit vanity mirrors, and the Berettas' headliner is low enough for me already... (Um, in short, NOT Aurora visors...

)