Yes that is it, I am not sure re 5/16 etc as it was fitted for me I will ask next Monday and take some photos of it on my truck as well over weekend and post up. I do know that they had to get from "joiners"/ ferules? made so it was airtight fit in the fuel line when they joined the fuel lines together as its a sealed system.
used it off raos lots of times as have pother people here and no problems with that either.
I see they now have changed the style of mounting etc a little and put a straight water trap up on the engine bulkhead and its up to you to check the water bowl for water. I see them on Ebay for US$ 131 plus shipping
Racor Diesel Spin on Fuel Filter Water Separator 30GPH 2 Micron 230R2 Marine MD | eBay

