I used it on my rusty floors when I first got my Bronco.
It's pretty old-school, but works to a certain extent. I can't say that it did a lot, but I had pretty substantial rust, and it did seem to clean it up a bit in the lighter areas.
Can't think of any reason not to at least try it.
For light rust too, I've been having great luck recently with "rust converting" paint/primer. You might consider a follow-up coating of that, after the Naval Jelly application.
Just bought 3 more cans of the paint tonight in fact. Made a Depot run and got one can of Rustoleum rust-converter, one can of Locktite rust converter, and one can of an unkown (but expensive) brand. Black, clear, and red colors respectively.
Will see if there's any difference between them. Painting rust spots under the hood, on Mom's washing machine, and various brackets and doohickeys.
Paul