Thanks guys, Got a coolant leak coming out the intake gasket so I decided since I'm taking the manifold off might as well.

 

Well Blazesters:
Just made a 1745 mile trip from -24 below zero in Minnesota to Bonita Springs Florida hauling about 2,000 pounds on my aluminum trailer. At Ocala, Fl it was 84 degrees, so that's a 100 degree difference. Did three 600 mile days without a problem other than burning up 142 gallons of fuel. Cruised 65 to 70 mph in #3 gear, and hardly knew the trailer was there,except for seeing the gas gauge needle on a constant move to the left. Yikes! burned up 492 $$$ in gas.

Blazer seemed to run good even through the hills and mountains from Nashville past Chattanooga, except for a constant strong gas smell noticed at fuel stops. Not really a problem inside the vehicle. Still having this problem down here at sea level and temps in the high 70's and mid 80's.

Pulled one of my spark plugs yesterday and found what appears to be the original Champions with a burn gap at .72 or something like that. A mechanic read it on his gauge and said he never saw a plug with that much gap. I didn't have my cheaters with to read the gauge, but I could see the plug was really used up. The Blazer has 145 K on it. As had as it was to get just one plug out, I can see why these might be the original plugs and why I may be smelling a lot of unburned fuel.

I purchased new Iridium plugs and plan to change them out tomorrow. I dread the PITA this is likely to be, but at least it will be warm and sunny out. I could use any tips on this process, and am going to review the forum now for some help. I am told to pull the wheels and go in from the side below, but it still seems like a bugger. Hope this does not go FUBAR on me. But, if I can get rid of the gas smell I might actually develop some admiration for this GM creature.
Wish me luck. If I blow it I guess I can go to the beach and drink some Margaritas.

 

If it had Champion plugs: #1 they are not original, and #2, with AC Delco 41-993 double Iridium, it will run much better, and help fuel mileage. They need .060" gap. Should be OK out of the box, but best to check them. DON'T pry on the center electrode. A little dab of antiseize on the threads helps the next guy... might be you Don't need to remove the tires, just jack it up by the frame and let the wheels hang, and work through the wheel well. #3 PITA plug.... several ways to go about it. I seperate the steering shaft from the gear box, 5 or 10 minutes to R&I the shaft, and you have plenty of room to change the plug.