Help - Cobra Trailer Top Lift Springs

Installed new gas lift springs purchased from Spindelberger yesterday
afternoon. Trailer is early 1990's aluminum top Cobra for a Discus.
Installation was relatively straight forward BUT I cannot get the lid
to fully close now. I am now stuck with partially open trailer.

One side is almost latchable but the other side will not make it down
and needs to go about 2-inches farther. Has anybody had a similar
problem? Could it be a defect in the gas spring under compression?

Initially it was difficult to get the lid to within 12 inches of
closing but after working it up and down for almost an hour it reached
a point where it would go no further.