My windows are really tough to roll down and up. One side lock doesn't work. How much trouble is it to replace everything inside the door and is there some info somewhere where I can learn more about it or should I leave this to the experts.

You can pop the handles and door panels off and lube the gears up try that 1st before the replacin' everything.

yeah it's pretty simple. Just take your door panels off and you will see all the screws you need to remove to grease everything

they're right, i'm not a mechanic by any right, but if i take something apart i confident i can put it back together again. so you're gonna' have to take those door panels, there's a clip that holds your window crank handle and one for your door handle, they make a tool so you can slide those clips out it's like $6. if you can't get one a pair of thin needlenose pliars can pull them out. if you can't do that a butter knife you can use to strech the clip out of shape. unscrew the armrest screws leave them in the armrest. then there is four screws on the bottom of the panel. after that the panel slides down then out now your inside.
i like to spray all moveing parts with white lithium grease with the spray tube on of corse then clean the window with a solvent.
if the door locks with your hand but not with your key that means you've got a broken piece, you'll see witch one when you get inside. you can get those parts for a buck at a junk yard. if the door lock wont move with your hand spray it down with wd40 when you get inside. if your key doesn't turn use spray graphite to losen the tumblers
you can get all of this information out of a 1967 c10-30 service manual. it will show you what the inside of your door looks like before you crack it open. you can get it through any chevy truck catalog. i usually find Truck Shop to be the cheepest, call 1800-chevy-47 and ask for a 67 catalog.
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