What are you trying to do, a compression test?
Had an oil leak coming from the oil pump drive\distributor blank, the o-ring was cracked and hard as plastic.I bought a new O-ring from rock auto and they sent me a pack of 5 for $1.49 =] I tried to find replacement O-rings for the fuel regulator and the other rail input , I bought 2 from GM for $20 that looked like they where not correct. I had a "kit" of nitrile O-rings I bought at Harbor freight tools some time ago. I thought nitrile O-rings were ok with gas, on the label on the box said not to use with aromatic fuels which I think means they contain benzene . Actually none of the O-rings looked like they were the right ones anyway. So I used the old O-rings, so I wanted to crank the engine over to see if it leaked, but I think just turning the key to on turns on the fuel pump. The good news is I went back to the HFT store today to use my free item coupon and a 20% off coupon and I found a "kit" of O-rings that are made of HNBR rubber and they are ok to use in automotive applications (says the label) and some of them look exactly what I need. Well there were no fuel leaks. Sometime in the future will replace all the O-rings in the fuel rail system they were starting to dry out but looked serviceable for the time being. thanks for everyone that answered, now that I think of it I think there is a relay that can be removed that disables the ignition.