no, you don't need the gauges for it to work but you do need a vehicle speed sensor (VSS) signal https://www.marlincrawler.com/transfer-case/parts-upgrade/misc-hardware/vehicle-speed-sensor-mci
you will also need to use a gas tank from an efi truck or modify yours with efi parts which will include adding a relay for the fuel pump, another relay for EFI and a return and vent line to the tank. i would retain the obd plug and add a check engine light to retain the ability to monitor and troubleshoot
Thanks for the info. I planed to keep the OBD and check engine light. I haven't decided which way I'm going to go on the fuel system yet. It will either be a cell or a Ford rear tank at the back of the frame. Either way I do plan to use an intank pump. This isn't my first EFI swap, its just my first Toyota swap and I found conflicting info on the gauges. I didn't think anything more than a VSS was needed, but I found reference to someone claiming that the gauge side of the ECM had to be wired in for it to operate correctly.
