well i have a 1972 and i've put over 12,000 in mine best thing to do is locate a 1971--87 front A frame swap it over i say find a 1971-72 better front ends it will have the 5 lug disc brakes get the rear end from the same truck put it in your now if yours is a leaf springs get one with leaf springs and the 1971--87 will work if you have coil springs only 1971--72 will work then i would rebuild will all new parts in the front end and replace the rear end grease seals and gasket might cost you in parts 600.00 labor cost you 500.00 but well worth it cus you get one stiff smooth handling truck then you work on the wiring by putting in all new facto9ry wire harnessess Stay away from pain less you get the full harness that dose the engine bay to the cab to the bed and you will never have a short and every thing is brighter

Now if you only have the heater in your truck there really simple to change out the heater core remmber to wash the box and clean it as good as possible paint and sand any rusted parts remmber to buy the heater deluxe kit that has all the new rubbers and gaskets and buy the breass copper heater core and paint the outer housing black for a true shinny it sticks out I say buy a new blower motor and the heater switch controler for inside your truck with new cables then your set if you really want to make it work really good buy a new radiator depeinging if you do a lot of hualing with it a 3 core will do just fine but if you live out in death valley get the 4 core radiator for extra cooling

Remmber to clean all your grounds so you don't get a short

one last thing if your windows are getting hard to roll up or down time to replace the window tracks and all the felt and rubber and channle stuff but that me