two add wires on positive and negative?

I'm thinking about doing the big 3 upgrade. Now looking at the battery terminal there is a cable from positive to the bolt on the back on the alternator. Check. Ground wire from negative on battery to chassis. Check. Now here is what I don't get.

1)Where is the ground wire from the engine block to chassis?

2) There are one additional wire on each the negative and positive battery terminals. Both lead into a single plastic tube what looks stright under the front of the engine. For 4th gen camaro guys you may know what I'm talking about.

I have a 1994 chevrolet camaro v6 iif that helps any.

Huh?  Please learn to write in sentences!

Often GM vehicles have the engine ground strap actually on the transmission.  But you don't really need to find it, you just need to install an upgraded ground at the same gauge as your main power cable between the alternator case (or your engine) and your chassis ground plane.  As far as your OEM wiring, there is no real need to disturb the factory wiring (unless you are building a show car or an SQ comp) just add your upgraded power and ground to what's already there.

Ok thanks DYohn,

Would it be ok if I were to cut the negative and positive boot and take the ring terminal on both of them off (assuming there is a screw behind each boot), keep the same wire, add them to the new neg and pos wire? Hopefully I'll be able to do that without actually cutting the wire and putting them on a new ring connector. If that's all I have to do it shouldn't be to bad.