Hi fergarb
There are total 3 types of Positive WIP and 1 Negative WIP that you need to reconcile with GL.
Following can be found from Report and you can easily reconcile with GL if you are using separate GL:
1. Material in progress - Production Control > Inquiry & Report > WIP Report > Material in progress (This is Positive WIP - Accumulation)

2. Indirect costs in process - Production Control > Inquiry & Report > WIP Report > Indirect costs in process (This is Positive WIP - Accumulation)

3. Work in Progress - Production Control > Inquiry & Report > WIP Report > work in process (Labor hours) (This is Positive WIP - Accumulation)

Last one in Finish Goods "Reported as Finish" > we do not have any specific report available in system. I normally take from production posting inquiry form with filter on Journal as "Report as Finished" and in advance filter Production Order having status = !Finished. This is negative WIP, as this is normally deducted from GL.

If you are not using separate ledger in that case, add all this data and try to reconcile with your GL, it will give you proper required data.
Let us know if this helps.
Thanks,