[LtCol Henderson Marriott]

Fox, LC Smith, and Parker Bros. among other fine American and English double guns have small re-assembly techniques and tricks-of-the-trade.
It might be a good idea to permanently post assembly/re-assembly detailed instructions
so marked under the Parker General Discussion-if these are not posted elsewhere. It might save time and in some cases Parker forends...along with hammers or extractors.
Measure twice, cut once.