Edelbrock makes a slightly thicker one IIRC.
Gzig5 gave you the correct answer and the move you should make. Regardless, this has solved 95% of all my carb heat issues. Hard start, fuel evaporation and heat soak issues.
We’ve had good results with the phenolic spacers (material feels like a rubbery composite plastic). They’re great for heat resistance and you can sometimes find adapter style ones that go from square to spread bore.
Phenolic resin is NOT a rubbery substance.
Phenolic resin is hard and stiff. It has the most minimal bending, twisting abilities. It is often called plastic. As in TQ carb center section plastic.
If you ever have your header off Wrap them! that will help as well.
Another trick, until you get the headers Wrapped. Get a 3/8 rubber hose. split it down the middle and slide it over the fuel line, on the fire wall, to keep the headers from boiling the fuel right there.
alu foil over that, will help a lot
EDIT the frame rail next to the header not the fire wall.
Good advice and the second step I would take. I would consider this an extreme measure and I have had to go there, Unbelievably so! But it happens.... LOL!!!!