I suspect that if possible that keeping the car on a conditioner could be less risky than extending high current wiring if starting after a period of lay-up might be the issue...?
Conditioner wiring can be fused thus if anything shorts out on the conditioner circuit the fuse should prevent any real issue..?
On the other hand if you extend high current wiring and if for any reason a short occurs then without a means of easy isolation (kill switch) chances are that a fire might start..?
Just thinking in type.
