I'm trying to have my drawing document units to use mm(in) and my bom to use inches in the cutlist. I was able to do it on one drawing by using bounding box length and it does what i want it to do but when I tried to do it to a weldment part the bom cutlist wont follow inches. I don't want to override my dimensions i just want the BOM to use the part/assembly units like i did for this pipe length. 

This shows what I want. Part units control the bom. Document units only change the dimensions

This weldment part is set to inches at the part level but BOM follows document. I am not sure what i changed in the first drawing that got it to work. 

Any help is appreciated

Thanks!