Product review (4 stars): how to install the spring
I looked all over the internet and found many comments on installing these parts, but no one tells you the position the spring needs to be in when installing! So now that I've messed with it and finally figured it out, I hope to help someone else who is spring-challenged as well.

To install the 8066018 spring for the lid of the detergent dispenser, the pin is going to go through the one hole on the base of the dispenser as well as both circles on the spring and then through the second hole of the base. When you slide the pin through, the spring should be positioned so that the square shaped part is closest to the dispenser and the two little wires that stick out from each side of the spring should be pointing down. Snap the lid on carefully, supporting the pin with your finger so it doesn't break. But be sure the spring stays in that position. Then, use something like a knife, a scissors or a flat head screw driver to carefully pull the square shaped part up and onto the little notch that is directly in front of it on the dispenser.

Perhaps I am the only one who couldn't see right away how to position the spring, but if there's someone else out there..I hope my description is clear enough to help you out!