extending the roof overhang

Whoever build the breezeway between my house and garage did a really strange thing. They didn’t extend the overhang out the same, it’s about 18 inches less overhang (see attachment). Weird. So, now there are downspouts at the end of the breezeway roof between the garage and the breezeway. I want to extend the overhang of the breezeway roof so it lines up with the garage, so I can eliminate the extra downspout and just run 1 continuous gutter to the end of the garage.

Unfortunately, shingles are normally put on starting from the bottom and working up. I’m going to have to remove the bottom couple of rows of shingles in order to attach the new longer sheeting. Is there anyway to re-shingle the bottom part without having to re-shingle the whole breezeway roof?

 

I put the filename of the attachment (a .jpg file) in, but it didn't show up. How do you add an attachment?