Thats the trouble with repop anything... Most all of it is JUNK!! There is always something that does not fit right and you have to modify it..
When Phil (SYC Member:Woj) and I were restoring my 69 Chevelle we were putting the gas tank back in the car. We were both laying on our backs holding the tank up and we started to run the long bolts into place that hold the straps/tank. The two bolts we were using were also from a "kit" and cosmetically looked "dead on" to the originals. We kept struggling with getting the damn things to start threading.
Finally after messing around with many attempts to get the threads started, Phil ran into his basement and came back out with two original gas tank strap bolts he had taken off a junk Chevelle at a junk yard out west, cleaned them and had them re plated. We used those and they threaded right in within seconds. We did nothing else different in the way we were mounting the tank and straps..
It was like the repro. bolts were just a "hair" to short to start threading. Needless to say those damn bolts went right in the trash!! It's just always something with that crap!!
Thats why we ended up using alot of original stuff on that car.. Makes a world of difference!!
Rich