I converted my 73 240D to the pencil style GP's. I ran a separate line from the battery. I used 10 gauge wire through a voltage relay activated by the new timer box. I had to install the new timer relay control because I had the old Gorilla knob.

I'm probably wrong on this but I believe you have to change the timer control from the loop type to the pencil style also.

There should be no direct power supplied to the GP's from the fuses.