1988 cutlass ciera electrical problems

Hey I purchased a 1988 cutlass ciera knowing there were things needed to be done but one thing I really want to figure out is the problem with my electrical system. I replaced the alternator myself. I bought a battery tester and the battery seemed to be ok ( should I get a load balance test to confirm?) I took a look at different resources to try to get a handle on why the charging system is not right properly charging. Some things I notice are

1. Gauges are really out of wack moving around and inaccurate.
2. There are a couple of missing fuses.
3. I bought a diagnostic connector and it said i needed to replace the
coolant temperature sensor and check the egr valve.
4. There was what appeared to be corrosion on the battery terminals
that screw into the battery.

At this point I'm not sure if its as simple as putting in the fuses and or replacing the coolant tempature sensor or as complicated as taking a multimeter to examine the entire wiring harness/electrical grounds. Based on the above observations does anyone have any input? I try to do what i can but i am no expert in this area. Any and all help thoughts pointing out glaring mistakes on my part is much appreciated. If you need any information on my part I will be more than willing to provide.

Hey I purchased a 1988 cutlass ciera knowing there were things needed to be done but one thing I really want to figure out is the problem with my electrical system. I replaced the alternator myself. I bought a battery tester and the battery seemed to be ok ( should I get a load balance test to confirm?) I took a look at different resources to try to get a handle on why the charging system is not right properly charging. Some things I notice are

1. Gauges are really out of wack moving around and inaccurate.
2. There are a couple of missing fuses.
3. I bought a diagnostic connector and it said i needed to replace the
coolant temperature sensor and check the egr valve.
4. There was what appeared to be corrosion on the battery terminals
that screw into the battery.

At this point I'm not sure if its as simple as putting in the fuses and or replacing the coolant tempature sensor or as complicated as taking a multimeter to examine the entire wiring harness/electrical grounds. Based on the above observations does anyone have any input? I try to do what i can but i am no expert in this area. Any and all help thoughts pointing out glaring mistakes on my part is much appreciated. If you need any information on my part I will be more than willing to provide.

Exactly what fuses are missing?
Why did you replace the alternator?
Check the belt tensioner

Ok I checked once again and there are the correct number of fuses in place I just replaced 2/3 of them with new ones. As for the alternator I assumed that that was the problem and didn't bother to get it tested autozone can be a bit rude around where I live. But as far as the belt tensioner I went by my Haynes repair manual that the belt should go no deeper than 1/2 in / 1/4 in depending on the length of the section Is there something else I should be looking for? I just replaced the coolant temperature sensor as well.

I had a problem with my 86 cutlass not charging. It also had a new batt. and alt. The problem was actually the hot wire from the back of the alt. that goes to the batt was bad. A new wire now, prob. solved.