You know, I've tried the fix with the 2'' and with the 1 1/2" cap and I can't seem to get it right.
The 2" I put on with the flat part up and tried to get the factory boot to fit inside the cap......couldn't do it. Then I switched it around. With the flat side down and the open en up, it's just sitting there on top of everything. I drove with it like that for about 2 weeks. The noise has gone away almost completely but the vibration noise is still very apparent under medium to hard excelleration!
This weekend, I went and got the 1 1/2" version. When i took the thing apart again, there was a lot of frayed rubber down in the hole.....I guess from the cap and the stock boot rubbing together. Now, with the 1 1/2", I put it on with the flat side down and tried to fit it inside the stock boot opening. I could just about get it all in there but, when I ran through the gears(without even driving the car)the cap popped out. So, whew.....lol, I turned it upside down. With the open side of the cap down and the flat side up, I managed to fit it into the stock boot. I'm still haveing the same problem. The damn thing is working it's way out again.
Is there something wrong with me or am I not doing this thing the right way again? Please help!

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04 Z06 Mil Yellow Mod/Red - Donaldson Blackwing, Power Duct, Velocity Stack, Throttle Body By-pass, Hood Seal, Hurst Short Throw Shifter/Billiard Ball Knob, Eckler's Z06 Partition, Random Technology High Flow Cats and X-Pipe, 170 Thermostat, LS1 Edit, DuraStop Ceramic Pads and Drilled/Slotted Rotors.