Fuel pump cm 2250 update help

[imalumberjack]

I have a cm 2250 and it came with 4 screw (bolt) head. The cm 2250 I think came with two different pumps the early years were a 6 screw (bolt) and later were 4 screw (bolt) all cm 2350 pumps were 4 screw (bolt). The barrel and plunger on 4 bolt heads between cm 2250 -2350 are different one has a orange o-ring one is grey (no you cannot just change o-ring)