Abstract: The mounting system for mounting the implement to a boom assembly forming part of a construction vehicle, such as an excavator, pedestal boom, and backhoe. A pair of spaced apart side plates include aligned apertures for receiving adapter plugs sized to be received within the apertures and for resisting relative rotation therebetween. Each adapter includes a transverse bore which is sized to receive a first pin member, such that each transverse bore is of an associated pair of adapter plugs defines the pin diameter that will be accepted, as well as partially defining the distance between a first pin member and a second pin member. Each adapter plug defines a flange portion having a surface abuttably engages a side surface of its associated side plate. The flange portions of an associated pair of adapter plugs define thrust surfaces for a boom member coupled to a pin carried by the adapter plugs. The thrust surface may be machinable to adjust the lateral spacing between an associated pair of adapter plugs.