Originally Posted by charmalu

The W123 has the block on the left fender by the battery with three screws under the lid. the SD has one also on the same fender, (location is a little different) just jump across 2 of the screws (one of the big screws to the small one) and this will by-pass the NSS.

turn key on, set parking brake, have shifter in park, jump across the screws and she should start.

Charlie