John,
If the actuator is too long fro the down stop either relocate the
aft end mounting or cut off some of the threaded end (within reason).
The uo stop can be positioned with some more nuts on the shaft or cut it
down a bit if too long.
Again, if 500 to 800 psi is pressure applied to the over
center link (main gear), that pressure is translated as a pre-load to the
point where the link is mounted on the spar. Additional load from a
bad landing can cause delamination of that mounting block (especially true
if you are using the hard donuts for suspension, high tire pressure,
etc.).
Good luck.
Scott
PS There is a service bulletin that describes a reinforcement
phenolic plate added between the top of the mounting block and the upper
spar cap. See if you can get it from
Lancair.