67 commando 273 issue

I rebuilt my factory 273 commando engine from the 67 barracuda I bought last fall. I have broke in the camshaft and lifters, set the timing etc and the engine runs and sounds beautiful.
Today I started the engine and let it idle to get another heat cycle into it while I tweaked a few things under the hood, and I noticed that when the engine is hot and I shut it off, you can hear fuel boiling inside the 4 bbl carb and if you look into the barrels you can see it leaking fuel down the barrels when it’s “gurgling”.
Obviously this is an issue I need to sort out for several reasons.
I can’t remember when I rebuilt the carb what type of base gasket was on the car, but now I am just running the thin gasket that came in the Carter bbd rebuild kit.
I’m wondering if it should have a laminated thicker insulator type base gasket on these 4 bbl commando engines?

I double checked timing, confirmed that the heat riser valve is working (I’m going to disconnect the exhaust and confirm that it’s not 180 degrees out).
I’m looking for advice on what my issue might be and other things I need to troubleshoot as having fuel boiling in the carb is clearly not acceptable.