I am hoping this post will provide me with a viable part number I can use to order a 12 volt overdrive solenoid. I am specifically seeking a part number that can be used at a auto parts store like NAPA etc. The type of solenoid I seek has a 1 inch shaft length when measured from the mounting plate. Its intended use will be in a R-11 Overdrive unit. Researching HAMB and other INTERNET sources there are plenty of references to using the existing stock of 12 volt OD solenoids to replace the OEM 6 volt units when converting to 12 volts. This information is usually accompanied with recommendations to purchase a replacement from antique parts vendors, usually at a cost near $300 dollars plus rebuildable core. Occasionally the provided information alludes to "over the counter" NAPA, AutoZone etal... units. It is this elusive over the counter replacement part's part number and source I seek. This month Hemming Motor News is running a story penned by the 5th Avenue folks which lists the part numbers for a number of OEM 12 volt solenoids Thanking all of you in advance.