Well done , Doctor.......I expect your prognosis is positive, but will the patient require therapy? (or is it the doctor that requires.........oh, never mind.....)
Re. the rear: duct tape the barrel well and scribe the base sides a tad (only a tad) high, try to cut at an angle to clear the barrel at center rather than just straight across to minimize filing. It'll be futzy, but when you get close slow down, or save for another session when you are fresh. With careful work you should be able to tell when you are at the brazing contact point, and have to barely dress that down since cold blue wont work on it. Stones are good there as they will give you polish too.