I did notice that the fit of the L.E.Ds I used was quite loose in don't instances, which varied from unit to unit. This resulted in the loose L.E.D going out. In the end, I fit the tightest units I had and but had to resort to using a thin strip of tape wrapped tightly around the base of the L.E.D to prevent movement.
Been several months now and no issues.
On another note, I also tried to replace my taillights with L.E.Ds. couldn't get them to work at all so gave up.