I did the rest of the first attach angle - and then cut and polished the second one. I used the band saw to a closer tolerance and didn't have to spend as much time working the polishing wheel, but I did have one dink of a cut that I had to polish out...but no harm.
I will measure and make sure that I am at the 2" distance mark on the rib - so that the tank attach bracket has a good fit at the point where it needs to be.