Classic/Antique Car Repair: 55 ford electric issues, ford fairlane, cable hookup

Question
I have a 55 ford fairlane that was restored by my father to original...I mean original..I guess that meant also to go with a positive ground system. I guess I should have known since the cable to the block was red and the one to the solenoid was black..  In the middle of having issues with the battery since it sat for a few years after his death, I got a new battery (6volt of course) and replaced it with putting the cables on with the neg going to the block and pos to the solenoid.  The car ran but I soon found out that the generator light was on and the car did not seem to charge even though the gen light would go off when the rpm's were up. As far as I knew everything else was still in working order until I found the brake lights not working... turn signals still did though.  After some poking around I realized that my battery was hooked up backwards. After hooking it up the proper way checking for a sparkless second cable hookup, I found that when I started the car the generator light is very bright and when rpms go up the light looks as if it is going to burn out it it gets so bright.  I disconnected the battery and now am asking for your help... thank you for any and all info about the electrical workings of this vehicle including the brake light problem which I may have damaged a relay or what is that on the master cylinder with the two wires... does that make my brake lights go on when i push the pedal...???  thanks.

Answer
Not to panic as these old 6 volt non electronic systems are more forgiving than the new 12 electronic and alternator equipped systems. Lets look at the stop lights first. If the directionals are working both front and rear that tells me that the wiring and the bulbs are ok. Now, the gadget on the end of the master cylinder should have two wires on it. Disconnect the wires from this stop light switch and connect them together. If the the stop lights now go on, this switch is defective and needs to be replaced. If they do not light then you will need a voltmeter or a test light. One of the wires should be live. If it is not you will have to go under the dash and find the stop light fuse. If there is current present it indicates a possible defective turn signal switch that will need to be replaced.
Now to the generator light. The generator needs to be polarized and should have been done before the engine was started after you corrected the reverse battery. With the engine not running disconnect the Field and Bat wires from the voltage regulator. Touch the two wires together of about a second, and then reconnect the wires. If the system still does not function properly then the voltage regulator has been damaged and will need to be replaced.