New member- 1976 Dodge Sportsman

I was gifted a 1976 Sportsman last winter. She had been sitting in the elements for several years, and has some leaks/rot. Mechanically she runs well, but needs some new brakes and some transmission work. The electrical system is a bit of a mess (have tail lights but no brake lights, wipers don?t work, etc). I?d like to put a new rubber roof on her to halt the leaking. I?m sure the windows need to come out and be resealed as well. Has anyone ever removed an aluminum roof and replaced with one of the rubber options?
I know this will definitely be a labor of love, but at least she was free. This far I?ve spent around $1,100 for a tow, new tires and instillation, a new battery, battery switch and some minor mechanical work.

Welcome,
You certainly have a labor of love to work on.
Some before and after pictures as you do things would be nice to see

Can't beat getting an RV for free. Unless the repairs add up to more than its worth.

You can apply Liquid Roof over an existing aluminum roof to seal it. It should last over 20 years. There are cheaper alternatives if you don't plan on keeping it long.

If it has been sitting several years, it could need complete brake system, all rubber hoses and belts, you mentioned transmission.  1976 there won't be a single thing 'non metal' that won't need replaced.  If you are decent with a wrench, that's great.  If you need to pay for much of the repairs and the labor, this could be one heck of a money pit.  Exciting times, but do proceed with caution.  Just to get it road worth, even for local camping, could costs several thousands.  I do agree that I would coat the roof first, great chance it will seal the leaks..  If everything else works out, re-evaluate.  Personally, I would be much more concerned with the mechanicals given the age.  Don't get me wrong, I had a 83 class C for many years, sold it maybe 10 years ago.  Things get brittle and break easily, and I feel mine was well maintained. 

Thank
You for the information. I?m definitely proceeding with caution. I promised my husband if Everton over my head I?ll let her go. I?m a DIY lover, but we shall see.

Please believe Spencer above. 
As soon as you can, collect the VIN (Chassis Number) and have it convenient.  The parts stores will be problematic with a vehicle of that age. 
Speaking of - "at that age", all the rubber - Brake hoses, Coolant hoses, Fuel lines, Door and HVAC seals  - will be junk. 
If it has been sitting long, you will need to be into the brakes anyway.  (You may have to learn how to open a truck rear axle.)
Be sure to use alcohol compatible material for the fuel lines.  The fuel tank will probably have to be dropped.   

Now, If you and yours are at all capable as technicians, you can do all of this with basic tools.  It will be about two weeks of evenings work, but without this, it will be nickel and diming (50 & 100$) for the rest of its existence. 

You will be replacing the coolant and brake fluid anyway because both have aged out.

When you can, look up a service manual for the Dodge chassis.  A good one will not be cheap.  It will cost as much as an hour of shop time.  Speaking of which, if you like this coach and plan to keep it, think about the fact that an hour of shop time is ~100$us most places (many are more), and for that money, you can pay for any tools you need to buy and have money left over.  You will also know how things work and what to do when they don't work. 

The manuals for most of the interior appliances are available on line.  Start a ring binder with the model and S/N of everything you can identify. 

Keep a record of what you replaced by name and part number as much as you can.   

And now your head is buzzing.....  To quiet that, yes, this coach can be made to be reliable and a lot of fun. 
??Does this guy know what he is rattling on about??
We had a 1979 Cayo Dodge for a while and now have a 1973 GMC that we have put a lot of miles on in the last 15 years.  We go wherever we chose without fear.  We did a run from Michigan to Florida this last spring. 

Get back to me if you have general questions (the Dodge has been gone a long time) and I will do my best to answer of point you the right way.

Matt