You might leave out the diseqc switch for the initial setup on your center bird.
That'll simplify things.
Whether the LNBs are Standard or Universal (must be linear), will make a difference on how you set the LO in the receiver.
Do you have a link for your LNBs and your dish?
I doubt you'll get birds 2º apart on that dish.
Most LNBs cannot be mounted close enough together.
Ya might get 99º & 95º, though.
87º to 99º is probably not an unreasonable spread
edit:
Just to get started, you could put an LNB directly in line with the arm, set your receiver to a
strong transponder for whichever bird you want to try first, then do an alignment.
Do look for a rising Quality on your meters. Signal strength alone doesn't really mean anything.
It's a lot easier if you take the receiver and monitor out beside the dish, too.