welcome to the site. Please, pics of the GTR would be nice to see what you have to start with. I'm hoping to get mine out of the garage in a few more weeks and start doing a little cleaning and maybe some fresh pics too!
Okay, I read the forum first and then saw you had pictures already posted. Looks like a little bit of work, but not beyond hope. I've got pictures posted showing how I cleaned out my gas tank - hopefully your's isn't too bad inside. And I also show an aftermarket fuel valve that I've installed. I haven't put gas thru the valve yet, but it looks like it should work fine.