I took apart my Brute set today for the first time since I bought them years ago to clean them. I got everything apart with the exception of the sight glass. Does anyone know how to remove it? It appears to just be threaded, but for the life of me, I can't break it loose.

Also, if anyone has any other tips for restoring them, I'm all ears. I'm already going to put new seals in the hoses. Is there any other readily-available seals for the valves? I know that Yellow Jacket sells a rebuild kit for them, but it's pretty pricy.