This actually opens the age old question...Is it the bill or the autograph?
Is a 36 year old 2 dollar bill in minty condition worth more than 2.00? maybe,... maybe not, depending on who you're asking.
If you are soley looking at the 2 dollar bill, it is damaged goods and not worth more than face.
If it is the Autograph,... Odd, different, interesting item to have autographed, then you are looking at what the autograph is worth.
I know when they grade baseball cards and comic books, the autograph affects the final grading. whether it be a conditional grade that includes the auto or the thought that the auto damages the final value. It is a subjective opinion.
I think it's really cool just to have that particular autograph.
Does it float like a butterfly or sting like a bee?