To frankr: If you look on marineengine.com for a Johnson JH-21 and look at the lower gearcase group for a standard drive, item #38 (part#0310355) is a 5″ gearcase extension. Here is the link: https://www.marineengine.com/parts/evinrude-johnson-parts-diagrams/JOHNSON/381410-GEARCASE-GROUP-STANDARD-DRIVE.gif
