Fred, assuming you have the #10405 harness from Jegs, it is really a simple modification to wire the ammeter if you choose that option. And as Jerry indicated there is no danger in using the ammeter if all is in good working condition and with proper wiring technique. Looking at their on-line wiring diagram there is a #16 wire that goes from the fuse panel to the starter solenoid. Just splice the ammeter in series with that wire. Cut it so that one terminal of your ammeter connects to the fuse panel and the other terminal of the ammeter connects on to the starter solenoid. You may find, as I did with my 59, that all is well without a shunt. If the normal operation of your truck seems to peg the ammeter more than you are comfortable with, you can just add the shunt later.
I would also suggest that you include a 14 gage fusible link in that #16 wire near where it connects to the starter solenoid.
Mark
