Mac install
A tube of anti-sieze for the new bolts.
O2 simms don't need to be different sizes.. They just attach to your stock rear 02 wires.
New GM manifold gaskets work best (metal).
New EGR gasket.
Two more AIR pipe gaskets, and restrictor plates to save your check valves from fluttering and burning up. I fabricated my own out of sheet metal. Great instructions: http://riptide63.homestead.com/restrictor.html
I went with "stage 8" bolts so they will never back out.
A torque wrench... Don't over-torque anything.. aluminum is soft..
Probably throw some new plugs (and wires if old) while you are at it. NGK TR55's seem to be the way to go, and they are inexpensive.
I also used a tiny air saw to cut off a piece of block casting to put my passenger side header in form the bottom (I could not get it to fit from on top.)
Sorry if this sounds like a lot of stuff, but it is better to be prepared...
Tommy <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
PS Air tools will help alot <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

