A-999 Swap and Information

i have a 1987 904/999 NON O,D with hyd lock up converter, no electrics needed for lock up,,

so if the BLUE wire is for lock up,,,what controls the locking up of the converter???? there are said to be 2 wire O,D trannys that only require a toggle switch to operate the O,D... how can this 3 wire be used in a non computer car it at all ????

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