This may not answer exactly what you need but might help @GregStiles. I had the same issue, the customer needed item level revision tracking. We had these options - only track the current revision using a UDF on the CI_Item file (and add it to BoM details and anywhere else you need it). Create a UDT with item reivison, release date, and current revision (as y/n). Or, make the revision part of the item number (which is easier now that we have expanded item numbers). They choose option one as they'd always kept a componenet revision history in an outside system with their notes, specs, etc. Adding the one UDF for the item revision to BoM details and anytime a component revision changed, in their world, the bill revision changed too. If it was temporary we'd use engineering control in BoM.