I'm assuming what your calling the intake gaskets are the stamped steel intake plenums bolted onto the head & receive air from the turbo via the y-pipe with the 2 silcone couplings.
If so, they are sealed only with a very tough grey sealant that is availible from Ford or International in a caulk gun stlye tube.
The tubes are date stamped with a best if used by date so once you find some try to the get the freshest goo.
Also the pass side is pretty easy to reseal with minimal parts removal but sad to say - the drivers side will call for the turbo to be removed to get at the back bolts.
(I cheated there & just did some heavy cleaning & resealing at the leak - knock on wood its held nicely)
Our early PSD's have 8 bolts holding the intake on & later models have 10 with the 2 extra bolts being where ours is a bit long between the bolts near the thinner end of the stamped intake which has helped eliminate some of this problem.
Travis made up some load spreader plates on Matts truck that worked really well & has held up to the high boost with no leaking that you may also try to help eliminate this problem.
MoreMPH has some pic in his sig of the spreader plates they fabbed up that may be helpful.
Best of Luck