Regarding the spark, as above just put a plug lead or the coil lead near an earth point and crank it, leave about a 2mm air gap. You should see a little spark. If not, remove the distributor cap and rotor and have someone crank it, you should see some spark activity at the points. The coil lead will be active here so be careful. The 1800 had a funky arrangement for power to the coil, you generally cannot see the power lead as it is encased in a thick cable that goes through the firewall to the ignition switch (I carefully removed mine and fitted another coil and ignition switch in its place). If nothing at the points then check for power to the coil, not real sure on how to do that, maybe there is a green book around that could help.
Actually, one test you could do is have the points closed, ie. on the flat of the distributor shaft cam - not the lobes. With the ignition on and the coil lead in a test position (2mm air gap to earth) use a medium sized flat blade screw driver and lever the points open (screwdriver between points arm and dist shaft) then let them snap shut. Mimicking the normal open and close of the points. You should have some activity, a coil lead firing or something should happen.
Check the fuses too, I recall there are only three of them for the entire car (!), pop them out and check they are Ok, then check they fit into the little clasps tightly. They are on the passenger side inner guard under a black bakelite cover that is likely branded Lucas.
There was a great showing of 1800s at the Aust National Rally on the weekend, about 12-14 1800s all parked up together right next to 10 Amazons. It was surprising how many were there, they all looked great!
