[Bad89stang]

O.K. let me persuade you to change your mind...
USE ULTRA BLACK RTV!
I have been down this road already and ended up doing the install 3 times to get it right. The first two times I used the rubber Fel-pro gaskets on the end seals and it looked like it was sealing during the install. After ten minutes of driving I checked and found a puddle of coolant by the distributor. Time to start all over!
USE ULTRA BLACK RTV!
Yes, it can work to use the rubber end seals. That is why Fel-Pro includes them with some of the intake gaskets, but don't roll the dice.
USE ULTRA BLACK RTV!
I was convinced that my intake was cast incorrectly and took it to several machine shops. They all said that the rubber seals are junk.
PKRWUD told me the same thing and he has yet to be wrong when giving advice to me.

Just use a thick, continuous bead of RTV and extend it up the corners of the intake gasket. That is all.