Removal of intake manifold

My rocker cover is leaking oil so in order to replace the gasket, i need to remove the top intake manifold.

how hard is it too remove?

do i have to replace the gaskets?

its a st182 by the way.
thanks

Haven't done it in a long time the if i remember correctly, remove the throttle body, remove the pipe connecting to the 1st runner and then i think its 6 or more bolts at the end of the runners under the intake chamber.
There are also brackets to remove, i think there is the one with the throttle cable, one by the throttle body and one behind the throttle body.

As for using another gasket i'm not sure, i reused mine and seems ok but depends on the condition of them i suppose.

I never changed my intake gasket but since then the car does feel sloppy, i'm suspecting heat soak.