I'm going to give my one and only design criticism for the 1800s.
The design and location of the gas filler cover and location of the gas filler pipe is a disaster and a potential problem for all of the 1800's out there.
If the seal from the gas cover doesn't fit very tightly on to the gasoline filler pipe, water will get into the tank. Regardless if you just wash your car, or are driving in the rain or any other condition which permits water into that area, and you have a worn gasket, be prepaired to drain the gas tank, remove the carb fuel bowl covers and suck the gas out, and blow the fuel lines out. Now this isn't a pleasent job if you are on the side of the road with traffic going 75+ miles an hour or even if your in your garage. Remember it won't take very much water to effect the running of that engine.
There should have been a rubber or soft sponge seal around the area of the gas tank cover so that the cover would close and seal the area of the filler pipe.
Short of puting a rubber cover over the filler pipe (which I've done with reluctance as I didn't find a gas tank vent and am concerned that the tank may create a vaccuum which would efect the fuel pump),(or installing a new rubber gasket which I have doubts about its effectiveness). do you 1800 owners have a fix? Surely I can't be the only 1800 with this problem.
Thanks, I'm Havinfun.