What the Scottish lads were used to was "fettling to fit", while the standard practice at the Ruhr factory was to reject any part that needed such "fettling" and get a replacement, while also reporting the discrepancy for corrective action further up the supply chain.
'Fettling to fit', rather than rejecting parts not manufactured to sound tolerances does seem to have been the norm in British aircraft and car factories. And we know how that turned out..