I don't think it is ever too late to supplement your test levels-in fact it may improve quality of life and diminish the ever controversial "male menopause".
As far as weight training, again it is never to late. In studies, relative strength gains (by percentage) actually improve more the first month in elderly adults that have never weight trained, than they do in a younger population.
i agree with tombstone
i think that supplementing with smaller amounts of testosterone would probably improve quality of life. along with a little exercise this would work well..........