Kevin - I think my carbs are about 1 to 2 deg off level and I have the transmission tail set up on the high side. Different manifolds are set up slightly differently.
There are wedge carb adaptors available and original Cobras apparently were at least sometimes fitted with them by Shelby.
carb+wedge+plates - JEGS High Performance
I think the smallest wedge plate I found was 4 deg and that was too much correction for my set up and with a smooth hood I was concerned about hood clearance. So I'm doing without for starters.
I guess you need to level your car up front to rear with a jack and see how much off level your carb is going to end up and see if it's enough to go with a 4 deg wedge plate. I believe conventional wisdom is it's better to have a slight forward tilt of the carb so that under acceleration the carb will level out as the front end rises.