I once worked on the same part for two different companies. I was the main fabricator at one company ( my fixture designs and processes) and just a welder for the other company. Contract was split that way to speed up delivery by the prime contractor. In the end, although both parts worked, they looked quite different and had to be assembled a bit differently.There would be even more issues if you had several companies making hard tops. This one is too dark, this one is too light, this one is too thick, this one is too thin, this one is too long, this one is too short. It would be a nightmare.
Obviously mine were the better parts, or at least I thought so.
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