Hey Jim,
FYI - If you're the original new purchaser of those, then IIRC they are lifetime warranty & you can send them to Koni for a rebuild/restoration. Otherwise, they'll charge a fee for it. Look them up online. IIRC their restoration center in in the Midwest.
I plan to have the 4 Koni's on mine that I got back in 1980 new (struts & shocks) restored by Koni, even if they only have perhaps 10-20K miles on them, but almost 30 years of aging on the rubber seals/etc.
Testing them before mounting is as noted above, but it's hard to put enough stress on them by hand in many cases, to get a good test. So they may still turn out to be soft & worn out once mounted on a 2200 lb. 914.
Cheers!
Tom
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