Moving the distributor vacuum line source shouldn't change how the carb works, but might change the engine timing enough to run differently. I've got a 1969 distributor on my '66 200 connected to manifold vacuum. It runs well with both a SCV 1100 and a non-SCV 1101.I took a manifold plug out and ran the distributor vacuum line to a fitting there. Then plugged the vacuum line on the carb. It was not happy and had trouble maintaining idle. Seems to of ran better using the original method.