Old age got me again. 92 ve reseal project and I have forgot how to reinstall the shut off lever in the pump top. Particularly, the shim size and O-ring size and position on the outside. Shim in on the inside but I can't see the details of the shims and o-ring size and placement for the outside of the pump. Does it use a small o-ring in the groove under the indexing ring or is it a bigger o-ring that fills the outside of the shaft hole? Any ideals or leads (or a big picture) would help. Thanks, Mike