I have a 1983 Datsun/Nissan King Cab 720 pickup and water anti-freeze is running into my cab. The other day it just burst and went all over the floor on both sides.
I have a Haynes manual, but it has very little details on the Heater Core removal and replacement.

I'm pretty good in repairing vehicles, but like to know what I'm getting into first. So, my question is "do any of you have information that could assist me with instruction for 1983 720 pickup heater core removal?"

I would really appreciate any help you can give me

We have some service manuals and parts thereof here:
http://www.nicoclub.com/archives/use-ni ... abase.html

I didn't dig into them. Please let us know if you find what you're looking for.

Welcome to NICO

Do you have factory air condition. If you do its a little more difficult. Remove the hoses for the heater in the engine bay. Next remove the dashboard - eight bolts, three on top, four on the sides(two each side) and one in the glove box. Unplug electrical jacks and remove the three bolts holding the heater/evaporator housing, pull out the housing and you;re done. You have to remember to take off the AC seal on the firewall to pull out the housing.