I disassembled the BBS on my '64 Valiant. After inspecting the parts, I am a little confused. First question: the float bowl and air horn mating surfaces are not flat. They seem to have a very slight crown to them. Is this normal or is my carb distorted? If it is, should or can I correct it? Second question: how much clearance is excessive in the throttle shaft? It "rattles" a bit, but not excessively. Is this too much? If so, any repair that I can do? Thanks!