I have a quick question. I disassembled a holey 4150 carb and didn't realize that two of the eight screws were different length. I am only used to seeing the shorter screws (3/4" under head length) but two of them are 1" under head length. Any idea what holes the longer screws are from? There two center holes between the throttle plats are blind holes and only fit the short screws. But I could have sworn one of the longer ones came from those holes. It is possible someone was into this carb before as I found the fuel fitting JB Welded to fix stripped threads.