Methods to use a tool for dimensional verification of a vehicle frame suspension system bracket pocket having first and second cam slots, the tool including a first sub-assembly configured for insertion through and registration of the first cam slot; a second sub-assembly configured for insertion through and registration of the second cam slot; and an intermediate sub-assembly disposed between and attachable to the first and second sub-assemblies via a shaft, the intermediate sub-assembly including an extension rod receiving feature defining at least one extension rod receiving aperture; wherein the sub-assemblies lock against the bracket walls to define a horizontal center axis and are adjustable to determine and register a center point along an intersecting vertical center axis between the first and second cam slots that is alignable with the at least one extension rod receiving aperture.