John,
Have you done the "dime" test?
+ Lift the spoiler cap and slip in 4 or 5 dimes.
+ Close and lock spoilers. If the cap didn't close flush, then the rod
length after the over-center mechanism needs adjustment.
+ If the spoilers did close flush, then you need stronger springs. The
springs on the ends should be about twice as strong as the others.
JJ