We've had post delivery work done at "Tramco" or BF Goodrich. The work was OK and to a satisfactory standard but the documentation was sketchy. We had to draft all our own manual revisions in-house working from very incomplete and sometimes inaccurate drawing data. Boeing are in the habit of sending aircraft direct to Tramco for post delivery work and airlines that can afford to pay Boeing to include post delivery modifications into their AMM and IPC there probably don't have a problem. I'd question what exactly is the behind-the-scenes tie-up between Boeing and this outfit. They got so big by operating at Paine Field and riding on Boeing's back, doing all the work that Boeing doesn't want to tackle on the production line.
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Through difficulties to the cinema