Torque wrenches are calibrated at a +/- 4%.
@6872xtc it's hard to get a good picture of the plug wire routing with the huge-ass compressor in the way. Hopefully my sketch will help, but this is what I've landed on.@mrk5 if you would take some pictures of the spark plug wire routing when you get to it, I would appreciate it. I looked at some of the Hooker headers, but I couldn't visualize how much of a pain it would be for the wires.
That was part of my reasoning for the flex pieces too. I'm hoping they will dampen some of the stress on the header flanges.I would add one. Vibration and stress when hitting bumps or holes in the road does funny things. I have never like hanging that much weight on the header flange.
So I asked my contact at Holley why the cutoff in 1974 for the Hooker headers, this is true for SBC, BBC, and LS swap headers in square bodies, this is what the product manager told him:
In early 2019 all of the headers that covered applications from 1974 into 1975 and up were split into two part numbers for emissions reasons. The original part number stopped at 1974, and a new part number was issued for 1975 and up applications that had catalytic converters. The parts themselves are still the same, just a different part number for the 1975 and up vehicles.
Yeah, I would say it's definitely some red tape monkey business.So I asked my contact at Holley why the cutoff in 1974 for the Hooker headers, this is true for SBC, BBC, and LS swap headers in square bodies, this is what the product manager told him:
This explains why we can't find the difference, there really isn't one.
I myself wonder if its just for some government red tape in certain states and they don't want to deal with it on the older models.

I know when I drill stainless at work, you have to go real slow and apply as much pressure as you can. I just use regular bits.I made a simple exhaust hanger bracket using a drop piece of stainless steel angle. It's not super strong but it puts some upward tension on the exhaust and it fits with the fuel and brake lines.
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I had to angle it towards the middle of the truck to keep the hanger away from the parking brake cable.
I also used a piece of stainless steel angle for the muffler hangers.
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The stainless we had is 316L. It was almost a bad idea to use because it was a b!tch to drill. Smoked a couple of drill bits, like as it turning red and literally smoking. Cutting fluid didn't help much even. Guess I needed better bits.