This may be a long shot but last year I had a very similar problem. Code 23 and 24 intermittently at first then happening every time.

The problem turned out to be a faulty accelerator micro switch. (1MS I think) It clicked solidly and I think I had already checked it with a meter. The voltage was very close to battery volts but there ended up being a 3 or 4 volt drop across the switch. This would have been enough to pull in a contactor on many systems but the EV100 picked it up as a fault and coded 23/24.

Good luck with it.

code 23 and 24 are related to the contactor coil circuits on the fwd and rev circuits.
since you have replaced all the contactors i guess we can rule out the fwd/rev coils being the problem.
I would double check the wiring between the fwd/rev coils and the pb4 and 5 connections on the card. Also i've found when there are connection issues between the card and the components on the control panel it sometimes can be found in the connectors themselves.
you can take a small pair of needlenose pliers and remove the plugs on the control card, take the needlenose pliers and go into the socket on the card and put a slight twist on the pins to improve connection. DO NOT twist them alot, but just enough to help make a better connection.
Also you can remove the 2 center filter rec's on the spiderblock and check the choke coil wire connection behind this, there will be a lone screw where 2 white wires connect in the choke coil circuit, make sure this screw is tight and holding the wire down securely.

Do you have a ev100 manual? If not search "ge ev100 manual"

This is a Hyster E60 XM f108v13408v