Even someone with those skillsets can make a mess of it..... My passenger's door gap proved that.
As has been said, everything interacts with everything else. But if you have the time and a high tolerance for repeating things, you could get a fairly good idea of what to do by looking at the whole thing several times. Get to know where ALL the bolts are,(under the fender,behind the door, down the firewall, behind the battery or washer tank....) and which direction things will move if you add/remove shims before you jump into it. And a second set of hands is helpful to, to hold things in place while you make those adjustments.
Best of luck, should you choose to complete the mission.