2bbl to 4bbl on a 318

I am switching my carb from a 2bbl to a 4bbl and have everything but want to make sure i got the correct intake manifold gasket.

It is getting the 600cfm performer by edelbrock with edelbrock intake

The car is a 69 dart with a 318, the motor is actually an 86 that was pulled with only 35k on it (at least thats what the guy said). I purchased an intake gasket set but it appears to be for the 4bbl option. Should i buy the 2bbl one since that is what was on it? Not sure how different they will be maybe i will just buy both and use the one that looks the most correct. However I am sure some of you guys know which one I should buy. I have to order the 2bbl one and will try to order it asap so i can install everything next weekend.

I believe it has the original 2bbl carter but what did they come with in 1986?

Thanks for your input!