Old starter  and new remanufactured  starter Comparison gauge set 
 
The Housing Comparison Gauge Set includes:
The 7200 Housing Comparison Gauge (right-Opening)  It is designed to compare old right straight mount starters with new replacement starters, The C508-7100 Housing Comparison Gauge (Left-Opening)It is designed to compare old Left mount starters. C508-7000 Housing Comparison Gauge  is an essential tool for auto parts suppliers and starter rebuilders. It is designed to compare old  Staggered mount starters with new replacement starters, allowing you to identify the number of shims needed to correct flywheel engagement. This gauge is specifically used on Delco starters, to ensure compatibility. it provides accurate measurements and saves time when selecting the correct shims for a starter install.