drivers side has gone - rusted away :( 
which one do i replace it with ? 1998 3door TDI ? paddocks have 2 - 
 Front Window Regulator RH - electric to MA137189 - DISCOVERY 1
RTC3814
 Â£34.00 ex VAT   
 Front Window Regulator RH - electric from MA137190 - DISCOVERY 1
CUH102300
 Â£22.95 ex VAT   
and how do i know which is the drivers side one and which is the passenger ??