I would create a quote with a dozen lines on it, use a saved search with all the line... fields as results and then mangle it up and watch what it does. I want to do this but haven't had a chance yet.

If we have a PK for the lines, then I'd always do a find, either with native SS2 or lodash (e.g.

_.find(so.item, i=> i.line == linefromSearch)

) then proceed with the line as normal