I feel your pain. I get so excited about getting stuff and bolting things together I forget to check the part over before I install it. Now I try to remember to open boxes as soon as I get the part and check it over, even if I won't be using it for a while.
When I was building my 427 I finally remembered to check out all the parts carefully before I installed them. As it turned out, I sent 2 lifters back because I wasn't happy with them, they had a tiny bubble in the forging.
At work I try to open the part at the counter when I'm selling it to the customer. 1) That way if it has something wrong, I don't send him home with a defective part. 2) If he takes it home and breaks it, when he calls back claiming it's defective I remind him that we looked at it together at the counter before he bought it. I've had some less than honest people try to stick me with something that they broke installing it, or worse yet, trying to return their old part in the box claiming that is the one that came in the box.
Also, if I get a part from our supplier and suspect someone has "tried" it before we got it, I immediately call the supplier and tell them will will try it but if it looks to have been used. You'd be amazed how often that happens on electrical parts.
And of course this had to happen to you on the weekend, as you say. It's never at a good time.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars (now converted to a "factory" 4 speed)
Had the same kind of thing with a new harmonic balancer on a 454 for a truck .
Fresh out of box, test fitted, pulled off the be cleaned and painted. Upon start up the damn thing wobbles very badly. Of course motor is installed now.
Must have got dropped somewhere in its travels from manufacturer.
