For the door I began by sanding it smooth to apply the new paint but also to see what other colors were underneath the white. The door had some sort of old graphic or logo painted on it so there were probably close to 6 different colors to sand through.
Once I had sanded to a point I felt was far enough, basically a point where I was tired of sanding, I got some brush-on Rustoleum colors, grey, green, blue , and white. The blue and white I mixed to try and copy the rest of the truck as close as I could get.
I brushed on the grey first, then green, and finally the lighter blue mixture. I let all these dry then began sanding these new layers until I felt satisfied with the look. So basically just a series of sanding, brushing, and more sanding. Really not much too it and you can't really do it wrong since it's not all one color anyway. The way I see it is it looks like at some point that door was swapped out with a door from a different blue truck.
And a small update from over the weekend, I got all the heater controls hooked up and working. The blower, housing , and heater core are out of a '72 F250 I pulled from the wrecking yard. I chose this unit for a number of reasons, the simple manual operation of the ducting, it only has defrost and floor vents, it's 12 volt, it mounts to a flat surface just like my firewall, it was cheap and heater cores(which I replaced) are cheap and easily sourced, and it fits under the dash.
I was going to use the control panel that came with it but it's kind of an odd shape to mount, basically a 45 degree surface that really needed to be flat and I would've had to cut the dash or make a bracket to hang it below the dash.
This got me thinking, I remembered that the pick-n-pull near my house had an old dodge D100 from the 50s I believe. I drove out there to see what I could find and luckily for me the dodge had heater controls very similar to the 48 Ford controls.
What really made this even better was that the cable ends attached in the same manner that the '72 heater unit did. I paid all of $16 for the knobs, cables, and panel; brought it home, drilled four holes to mount it under the dash where it would've been mounted hooked up the cables and I was done.