130 bucks from apple hydraulic for a rebuild of yours. The older manuals show the procedure. But special tools are required. They want you to check the bore and shaft. Shock needs to be replaced if they're bad. Oversize pistons were/are availble for the rebuild. The special tools hold the spring open for inspection and repair, there's a special drift and support to facilitate removal and installation of parts. Nothing that specialized though.

http://www.applehydraulics.com/delco.htm