As far as i'm aware, the 2 lights on the dash are engine oil pressure for one, the other is hydrostatic charge pressure and hydraulic oil temperature.
The easy way to check is to remove the sender wires for them one at a time. Start in the engine bay, remove the oil pressure sender wire. Ground it to the engine and watch to see what light turns on and off, this will be engine oil pressure. It should be lit when you turn the ignition on and go off as soon as the engine starts. If it does not go off, you have a bad sender or low oil pressure.
Now the other senders, lift the cab, trace the wires that come from the harness to the port block, i'm un-sure what style machine you have so just trace the wires. The wires should connect to 2 senders, one is temperature the other is pressure. work it out the same as last time. Find out what sender is bad and what light does what.
As far as i was aware, they never put an alternator light, not as stardard at least the previous owner may have instaled one though.
Any other questions just yell.