I am trying to find the correct part numbers for the gas springs for both rod box lids. the ones on there have numbers but I think they were changed years ago and don't know if they are correct. the port box is a SpringLift SL-30-20 and the starboard is a SL33-20-1. I have looked and there are so many different ones with many different lbs of force. just want to make sure I get the right ones. Thanks