1955 starter solenoid wiring

[MJB1]

Just doing a 6V to 12 V conversion on my 55 and on the kit I received the new starter solenoid has a S terminal and I terminal.
The existing 6V solenoid only has a single small terminal and there is a wire that goes from that terminal to ground down on the engine block.

Now that I am changing from positive ground to negative ground and installing the new solenoid as per instructions I am
not sure what to do with that ground wire going to engine block.
Is it ok to leave off. I cant seem to find any info on what to do with it.
Thanks

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[doug7740]

The "I" terminal is for the ignition. Run a wire from the "I" terminal of the 12V starter solenoid to the battery terminal of the coil. Remove the ignition wire that is presently attached to the coil and add a new wire about a foot long to the bat. terminal before securing the nut. Now connect both the new wire attached to the bat. terminal of the coil and the original ignition wire from the ignition switch to a new ignition resistor.

doug7740
1955 Thunderbird Blue

 

[MJB1]

The "I" terminal is for the ignition. Run a wire from the "I" terminal of the 12V starter solenoid to the battery terminal of the coil. Remove the ignition wire that is presently attached to the coil and add a new wire about a foot long to the bat. terminal before securing the nut. Now connect both the new wire attached to the bat. terminal of the coil and the original ignition wire from the ignition switch to a new ignition resistor.

doug7740
1955 Thunderbird Blue

So the existing wire going from the single terminal 6 v solenoid to ground can be eliminated. Thanks for that info

 

[doug7740]

The existing red/blue wire that is connected to the single terminal of the 6 volt solenoid originates from the "S" terminal of the ignition switch and should be connected to the "S" terminal of the 12 volt solenoid.

doug7740
1955 Thunderbird Blue

 

[MJB1]

Thanks for the wiring diagram and I should have mentioned I am using an alternator for the 12 volt conversion.
It is one that looks just like a generator but is a 90 amp alternator.
It turns out also that the wire that I thought went to ground from the single pole on the old 6 volt solenoid actually goes to the neutral safety switch on the auto transmission. Thanks again for the help.