Installing Shark 2 Antenna

[Silver]

Ive been trying to install this antenna for like an hour now and getting very aggravated. For one, am i supposed to be using the washer that came with it? Ive been trying to get this thing through the little hole in the trunk and its ridiculously hard in this tight space. Any tips?

[Polygon]

I used an extension with the correct socket with the nut inside. It was still a PITA and took about 20 min to finally get it threaded but it worked. To keep the washer where it needed to be on the nut I used a small dab of grease to keep it from moving.