There are inventory stock types specific to build for stock and assembled items. The QuickBooks Integration setup has sections specific to these stock types where you can assign asset, COGS, and income accounts.
Like assembly, parts consumed from inventory for build jobs will use the Assembly/Disassembly posting account as a pass-through (see the QuickBooks section in the User Guide for more information.)
Finalized posting to assets will be done when the build job is marked Done (which in turn marks the status as in stock).
For more information on QuickBooks: