HiCustomer I see that glenn is offline, so I will step in here to help you get the pump floats wired. It's never a good thing when the septic system is down, so you have my sympathy.
I read the entire thread between you and glenn, and I found what appears to be a contradiction. If the floats are wired in series, BOTH floats will have to be up for the pump to turn on and if one float goes down, the pump will shut off. You stated that one float is like a backup in case the other float fails to activate the pump. In that case, you want to wire them in parallel, not series. If the floats are wired in parallel, then either one going up will turn the pump on, but both will have to go down to turn the pump off. I can tell you how to wire it either way, and you can decide which type of circuit to use.
To series the floats, bring incoming power (hot) to one float lead, tie the other lead from this same float to one lead on the second float. That leaves another lead on the second float. This last lead will connect to the hot lead for the pump motor. The incoming circuit neutral needs to go directly to the pump.
To parallel the floats, connect incoming hot power to the black leads for both floats, and connect both white leads from the floats to the hot lead on the pump. Incoming source neutral again needs to go directly to the pump. If any of this is unclear, just let me know, and I will be more than happy to clarify for you.