I found an old homelite XL 12 chain saw in grandpa's garage (grandpa died last year) and decided rebuilding it would be something constructive to do. I have no idea how old it is, the plate on it says XL 12, serial # 1987198P. Now that I'm done, before I fire it up I'm wondering if the fuel mixture is 50 to 1 or 32 to 1. Any ideas? Plus any other things I should look out for when dealing with these old saws?