Hey Chris,
Glad to see you got the car out on the road, it looks great in the pics:f. As for the running issue, I have some thoughts. When I tuned it last winter it was running great but now the weather is much warmer, so it may need some minor adjustments. I don't know if you want to tackle this yourself or not.
I set up the mixture and timing so that it would start easily in the cold weather so the mixture may be too rich now that it is summer. When the ambient air temperature is cool the air going into the engine is more dense and requires a bit more fuel to run at it's best, now with warmer, less dense air the engine will require less fuel. This will be most apparent at idle and just off a stop when you first put the pedal down. The engine may be loading up with (running rich) petrol. Also the float levels may be a bit too high. Welcome to the world of carbed engines.
Adjusting the idle mixture only requires a flat blade screwdriver and a steady hand. If you want to email me or Rochelle, I can walk you through it. Beyond that things get a little more complicated i.e. timing and float adjustments. I will help with whatever I can.
Heat could be a factor, but it has an electric fuel pump which should keep up with the engines demands and hopefully help prevent vapor lock. One way to check for fuel flow is too look at the fuel pressure gauge I mounted on the fuel line next to the carby, you may have to remove the air cleaner to see it clearly. It should read between 4 and 7 PSI, if not, the regulator may need adjustment which is next to the fuel pump (below the washer fluid bag). This requires a spanner and an allen key to adjust, you must loosen the lock nut and adjust the screw. I can send photos of anything you need to use as a reference. This should not be an issue but it is also something to look at.
Also check under the grille, I fabricated an aluminium bracket to hold the front number plate. I left a comment about this on the tech forum post you made.
Later,
Kevin