The main issue I'm having is that there doesn't seem to be enough suction of fuel into the cylinders.
To check if gas arrives to the cylinders can be tested by removing the sparkplug and see if they're wet. To see if gas arrives to the carbs or not, is easily tested. Just open the drain screws. When nothing comes out, there is a problem. You could drain the floatbowls and leave the drainscrews out for the next test. With your ear near the drain opening, you must hear it hiss, when you crank the engine. BTW, were the slides high enough when you tried to start? Do the chokes function OK? How old is your gas?
Timing the ignition is done
after breakerpoints gap are set correctly, that is between 0,3 and 0,4 mm, this to be measured when they're opened at their widest. I don't know if you had the points of, but always check that none of the spade connectors on them accidentely touches the plates and so makes ground. After you have set the ignition timing, always double check preferably without using a wrench, but by slowly pushing the kickstarter. Are condensors still OK? A little sparking at the breakerpoints is normal, excessive sparking however is not good. See
Left condensor (1+4) is bad, right condensor (2+3) is good.
