Thanks AVB. My mechanical skills are known to have made items unusable, so might best be left to a professional. I've taken base off the air filter so if you could point me in the right direction I could find it, but won't waste you're time if you're in the middle of thanksgiving!
I'm looking at keeping this mower for the foreseeable future so as I said in my first post, so budget wise if the cost of replacing the carburetor is OK then it might just be easier doing that...