My Megasquirt adventures over the years

Do you have any advice on how to set up a MS3 gold box to control spark only? I found one for a great deal and was going to use it on my stroked 6.1 hemi, that I am putting in my 70 plymouth duster race car.
My opinion is you'd hook it up like you were going to do it with fuel and then just not connect any of the injector wires. I don't think it would care too much honestly.