Couple of question

[f18delta]

Just got this 85 GMC 3/4 ton a couple of weeks ago. Since then, I've been doing an inventory of what I need to get done to it so I can make it my go to when snow and ice hit. Short list is as follows:

Immediate needs:
Heater core swap
Figure out why blower motor was working and now doesn't
Fix drivers side window being stuck after rolling down
Change rubber on doors/windows

Other stuff is cosmetic:
Redo seat foam and covering
Replace jute and carpet/rubber mat or pull it all up and spray bed liner inside
Fix blinker cancelling mechanism
Replace steering wheel and fix horn
Drop some height

So here's the questions....Anyone got a good reference book or web site with pictures to replace the heater core?

I know there's a site that has a bunch of wiring info and diagrams, so I should be good with troubleshooting the blower motor.

Drivers side window seems to have had the screw holes oblonged. A friend of mine suggested a small strip of steel to tack on with a welder after marking holes and reusing screws if long enough. Any better ideas? Not worried about the cosmetic aspect of this because it will all be hidden by the door panels, but worried about possible warpage. I'm an official 4 bead welder....And all 4 were ugly! LOL

Think that about covers the initial problems and should get me through the winter. After that, I'll be researching the other cosmetic issues. Anyone think this would be better as a build thread? Even though there's not much building to be done....