George .... in an ideal world they would have had a dedicated ecu for both types of gearbox ..... my guess is the loom wasn't custom made either and when doing the 'conversion' they just found a spot on the loom where the black/orange broke out of the wrapping (probably for a connector) and spliced the resistor in at that convenient (and out of sight as 'bodges' go) location .... it's what I would have done. Just a guess though.
K