How to split parts in assembly mode?

[Anautics]

I have an assembly of several parts and want to split some of the parts and then delete them. Referring to the attached figure, I have several parts which go past a rectangular frame which I've defined. Is there any way I can "delete/trim" these excess parts?

Thanks

[RoyHandley · Accepted solution]

Hi Ryan

Could you create a new plane on the top surface of the frame, draw two rectangles as shown and extrude them, removing material in the direction of the diagonal strips so that they are cut away?

Roy