Header Gasket size

[sgr60]

Hi all -

I'm looking to order the best gaskets I can for my upcoming swap to hooker headers. I'm looking at the Fel-Pro Performance Exhaust Header Gasket Sets.

There are a lot of options - square or round port, and size.

I believe the block ports are square, but the header ports are round. I read (I think) you should match the port - so I should go with square. Just want to confirm that.

Next is size - does anyone know what the correct port size is? I'd written down 1.5"x1.5" but that sounds too round a number to be right

Just want to confirm everything before I make the order!