Volvo Repair: 1976 245DL, gas gauge, mechanical skills

Question
I hope it is okay if I fire a few questions at you. First I just bought this car for 120 dollars, so i'm willing to put some money and time into making her run right. Right now i'd like to change the rear brake pads, which are squealing something fierce. I understand the fronts are no problem but the rear ones might be a bit tricky, so i'd like some advice on that. Next i'd like to fix the door handles, they don't open from the outside, but work fine from the inside. Also I'd like to get the Odometer and or gas gauge working, really I just need either one which ever is less complicated and expensive, so I have some idea how much gas i'm using. Lastly the heater does not work, it just blows cold air, I think it is the heater core, and I just want to know if that is a complicated job, or if it something I may be able to tackle.

I have some experience in minor mechanical skills, and the Car's odometer is frozen at 122,265 but I suspect she has more miles than that. Feel free to answer one or all of the questions;

THanks so much

Taran

Answer
Hello Taran,
  Rear brake pads are very easy...you must have good working calipers to get good brakes...if pistons are frozen...front or rear...get  rebuilt ones...pads must fit freely in caliper and NOT cause drag on wheel...at least not to any large extent...if you jam a set of pads into a unknown caliper and drive off into the sunset...you'll almost always will have a problem...on some ocassions brakes can catch on fire...so Taran...get into the job and know that the parts are in good working order...betcha 5$ the e-brake dosentwork...that is a another story...
You may have to replace discs too...get parts on internet...super good prices..you'll be replacing brake lines that go into caliper...maybe...
....Door handle...usually a pin falls out of the door lifting arm....easy fix.....carefull remove door panel..on door tray is securing hardware that hold tray....find heads of pins located on bottom...maybe 3 of them...when you find them...make the slots go ..up ...them pull out pins...or you will trash the door trying to get in...Theeeeeere are so many little parts of this project that you will just have to use common sense to figure..
Heater....look on floor area of drivers area...look up to the upper right cornor...see a water hose...it is connected to hot water control valve...watch to see if it opens to the max...you may have to move control arm with small pair of vice-grips....another reason...no thermostat...radiator water too low...
speedo...the cable connects to the back of dash cluster..find cable with hand under dash...get it disconnected by squeezeing the housing.....with speedo cable in hand...drive car...if it turns...bad speedo head...they were a problem...sometimes..the cable falls out of back of speedo...if cable is stopped....something down below isnt working....cable...tranny speedo drive gear...
Gas gauge....sometimes its a constant volt reg...on the back side of gauge cluster...pressed on...you're gonna have to figure out how to get dash out...easy...under light switch is screws on left side...youll figure out the rest....other problem...gas tank electrics that send signal to gauge is trashed...probably rusted out connections on top of gas tank....this is likely to be the cause

          Gotta go,
              Bilbo