I moved this from the General forum to the Distribution, Manufacturing, and Applications forum so you may get additional suggestions as well.

Have you tested using Option Bills?  You can make the interchangeable item an Option so you can add or delete the item depending on the desired configuration.

You can build the assembly with 24 parts + material and labor and complete it to inventory.  Then, you can create a BOM for another part that uses that assembly plus another assembly for example.   BOM's can have multiple levels.

I may have asked the wrong community as I am using Sage 100 Contractor, not Sage 100....very new to the product and not sure of the difference, but will look into using BOM's if I have the capability.

Sage 100 Contractor is under the Real Estate and Construction of this Community Hub; you asked your question in the wrong area.  

Sage 100 Contractor is under the Real Estate and Construction of this Community Hub; you asked your question in the wrong area.