Northstar - Change valve cover gasket
 

I have a 93 Allante and I'm leaking oil from the valve covers and its stinking up the place pretty bad when driving. :)

How hard is it to change the valve cover gasket on these early northstar engines? In particular, it's primarily the back one which I assume is the hardest to deal with. Is it something I can tackle on my own or is this something I need to leave up to my favorite mechanic?

This is one better left to your mechanic. It is not impossible but it is not something you want to do if you are not familiar with lowering and raising your engine as well as rotating it away from the firewall.