67 twin turbo dart

On mine I had to go to a Hall effect sensor. The magnetic pickup was not very consistent. Not sure what style you are running.
Its megasquirts old style hall effect, these require a tighter gap, so the shop is going to strengthen the bracket (its a single bolt mount) make it a two bolt, then close the gap tighter. DIYautotune is out of there new style and not sure when they will come in which the new ones don't need as tight of a gap. So that will get done today or tomorrow and they will out it back on the dyno and try again. Hopefully the closer gap will work and can go on to the tuning to the different fuels.