I believe JB Weld will work fine as an insulator / potting material in a 12V system.
The only thing I can think of that you might watch out for is ganging one 6-way block serviced by a single ground wire...ensure that you don't have too many of the circuits you are grounding engaged at one time such that you overload the single ground wire. Or make your single wire that services the connector a slightly larger GA to compensate.
IIRC, on the stock harness, the maximum ground wire grouping was 3 conductors.
The only thing I can think of that you might watch out for is ganging one 6-way block serviced by a single ground wire...ensure that you don't have too many of the circuits you are grounding engaged at one time such that you overload the single ground wire. Or make your single wire that services the connector a slightly larger GA to compensate.
IIRC, on the stock harness, the maximum ground wire grouping was 3 conductors.





