I put this on both Plymouth bulletin and P15D24 forums, as I got valuable help from both:
I resigned when planning 6 to 12 V conversion. It seemed too pity for me to replace all of the 6 V assemblies (wipers, fans, roof motor, generator, regulator, radio (??), power antenna, fuel gauge etc.
So I decided to put another ready to install 12 V generator to feed my 12 V 6 Ah Gel- Battery. From this, a lot of accessories are powered: modern radio (in Europe are only very few AM stations remain, here I get only one dutch!) GPS unit, power quarter windows, radiator fan, tachometer, and to come power steering compensating for my deteriorating right hand?s abilities.
My mechanics built me a new generator bracket fitting the existing threads in the engine block, fixture for 12 V generator lowest (with setting arm).
For the original 6 V generator they provided a place to fix the original bracket without modifications. The setting iron strap is new for not modifying the original one.
A longer tooth belt (they said: less wear when twisted around 4 pulleys? ) and 3 cables was all.
I even can set the right tension with the upper 6 V generator only without changing the mid position of the lower.
At this time, I found the very sharp edged emergency brake lever bending and damaging the original wire harness heavily! So, this spring, I had to redo the harness in partially. I was able to get very nice oldstyle but modern high quality wires in every size. At this occasion I could redo all my paraphernalia wires too. Now, I have a very nice harness with a couple of oldstyle fuse blocks for safety and easyer error searching.