Steps to change a spark plug

SOURCE: 01 Chevrolet S10 Blazer hesitates/misfires

If it is only doing this in overdrive lock up, tap the brake if it quits see a transmission man your torque converter might be bad

SOURCE: how to change 2005 chevrolet equinox back spark plugs

With all due respect for the opinion - I suggest you will do it better working from the underside for the 3 on the rear of engine.
Four points in your story motivated me to try from the underside (and I just finished the job without any hicups):
- mechanics suggested from the underside
- 130 lb sitting in the engine compartment will likely damage or crack something
- removing the distributor should not be needed
I drove the car with the front wheels on a pair of inclines to get more clearance underneath, secured it, then squezed from the front between the wheels. A good thin flurescent light can fit from the bottom up to help you see what you're doing.
The boots from the spark plugs I removed without much effort, then with fingertips I felt the exact place of the plugs. I fit a short 3" extension over the socket, then squeezed the handle and started turning. All theree came out without problems (before removing completely I also squeezed the extension pipe of a can of compressed air and blew air to clean around the plugs).
You need to "see" with your fingers and remember how the plugs are inclined to fit the new ones, but otherwise is just a little exhausting that you have to be a contortionist and find a good position (something to raise your head while working underneath, like a cardboard box would be useful).
So the bottom line is that it works as well from the bottom and don't have to remove anything else.
Pabloantoine

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SOURCE: Need to know the placement spark plug wires 2001 chevrolet malibu

do not have a diagram, but heres the firing order. 1-2-3-4-5-6, 1-3-5 is in back, # 1 is closest to alternator. from left to right, or facing engine from front 2-4-6 is in front. 5-2-3-6-4-1 is coil pack, from left to right (facing from front of engine).

SOURCE: whaT IS THE EASIEST WAY TO CHange the back spark

The easiest way to change the back plugs on a GM V6 is to pay someone else to do it. You need good light, good tools, lots of various extensions, swivels, and universals. A good vocabulary of curse words also comes in handy.