If you losen off your primary screws and look into the primary cell you should be able to see the springs around each primary screw. Just take ONE screw out, pull out the spring, then reverse the procedure with the new spring and screw, then move onto the next spring. DON'T remove all springs at one time or its a real %^^$@# to get it all back together.
You will have to collimate after this procedure

that is for sure!!