Just did this last week, I had oil dripping lightly off the oil filter and a little at the front end, when I looked up at the drivers side head and valve cover it looked as though it was coming from around there. On reading up it seems the lifter valley is renowned for leaking and in my case it was. [I replaced the oil pressure switch almost a year ago, plus it felt dry].
Limited to what I can get here but I got a Felpro kit which has both intake gaskets, a throttle body gasket, a small tube of silicone, the injector seals and some gasket I couldn't locate!
For some reason the 2 egr gaskets on the back [LT1] are not included, I was lucky mine stayed intact, but if your doing one I would have them handy.