FelPro 1211 or 1275 gasket?
 

The 1211 is used if the intake / heads have the extra upper bolt holes between the intake runners. The 1275 does not have the bolt holes. My Performer RPM Air gap has the provisions, but my Dart intake doesn't have them. Can I play it safe and purchase the 1211 and still use it with the Dart if I decide to go that direction, or will I have an issue with a leak? Conversely, if I go with the 1275, would I be able to run my Performer RPM with it?

Heads are GM 088 castings.

You could just get the 1275 w/o the holes and if you decided to use the air gap cut them in yourself. Personally I would wait till I decide and buy them then.

I wanted to get everything together at once so I could get on with this project. Was hoping to order all the gaskets from the same source to save some shipping costs. Might go ahead and get both and send back what I don't use.

Has anyone run the MrGasket Ultra Seal 5828 gaskets? They look like a nice piece from the pictures. Did notice that they are double thickness - .120 instead of .060. Wonder if this would cause any alignment issues or put the distributor up too high for proper gear mesh?

Jegs says their .060"?
http://www.jegs.com/i/Mr-Gasket/720/...rentProductId=

5818 is the .120"

oops - good catch, Jim. Also, 5819 is the thick one without the bolt holes.

Is there any advantage to running the thicker ones - maybe better sealing due to more compressible material? Or will it cause issues like I mentioned with distributor drive gear alignment?

Don't think it would effect the distributor gear to a point of issues. I believe you use the one which gives you best alignment with your heads if you have had them resurfaced or block decked. Don't know how much of that you've done but sure you need the .060"? More machining-thinner the gasket. Can get to the point where milling the intake is necessary.

I like Mr. Gasket 121's or 122's.