Installing your Dakota instruments should be pretty straight forward - as you already recognize you will have to install a Hall-effect drive sender for it, then also identify all the correct wiring colours for the idiot lights & wire those accordingly. Hopefully you have a copy of the electrical schematic.
I installed a digital drive speedo in
this thread - you could use pretty much any sender device, even the one I used. Does not have to be the same model to match your Dakota. Another very clean method would be to use a Speedo Sender from a Triumph Sprint (up to 04 models) - that is a form/fit for your wheel (same fit as your mechanical unit) and easily installed - has three wires, power, speed signal output & ground. Just a consideration if you can find one used on EBay (they are quite expensive new at ~ $170)