Pay attention, 007!
73a was asking about replacing his knackered four wire alternator with a three wire alternator. I was talking about joining two wires on the THREE WIRE alternator that 73a has been given, not the four wire alternator which he wants to replace. Indian alternators pre-1999 were copies of the Lucas RM19 (ish), which to give the full output required for 12V need to have two of their THREE wires (whose colours I could not remember) joined together, I would suggest using proper terminals rather than just twisting bared ends together... It probably already has 4.7mm bullet connectors.
The four wire alternators can be converted to put all their output through the reg/rectifier according to Pete Snidal's manual, but that's irrelevant here, since 73a posted that the original 4 wire alternator is u/s in this case.
A.