Reamer setup for Rib-to-bulkhead holes

[bkthomps]

So my main bulkhead spars are in and riveted, the downside is now I am trying to install the AN3-10A bolts (16 in total) in the top and bottom of each rib, but the holes need to be reamed a bit it seems.........any ideas/plans/thoughts on a right angle or 45degree reamer setup that is only about 1" long? all of my reamers are 6" in length and I'm really scratching my head over how I"m going to enlarge these holes enough