A real redneck can just smell the exhaust on a pre-emission vehicle and know whether it's running rich. Look for black smoke, sooty tailpipe, sooty plugs, and a raw smell to the exhaust.
My attempt at rejetting a '76 FJ55 carb was disasterous - I used one-size bigger jets and it ran very rich and crappy and was undriveable. I know even less about rejetting a Weber carb. My '78 FJ has stock, sea-level jets and only gets rich and boggy around 12-14K feet of elevation, where I too-rarely tread with it.
Anyone doing all this would ideally have access to a factory emission manual, a timing light, a vacuum gauge, and ideally, a CO/emission tester.
I would work on timing first, and then worry about rejetting. A sea-level setup on a good carb will run ok at 5000' (Denver) and you'd rather be too rich than too lean (from a valve life standpoint). Get the timing right, drive it some, talk to others, and only then worry about rejetting.