I have just received my father's split bamboo fly rod. It is a 9 ft. Montague. Part of the label is scratched off, but what I can read says PELH-- Brook. I have seen listings for a Pelham Brook from Montague, so I assume that is what this is. My problem is, I don't know what line weight to use on it. The line on my father's reel is probably the original line he put on it back in the 40's. How can I determine the line weight for this rod? Thanks for the help.