O2 sensor #1 is before the cat, right at the top of the downpipe, but the vacuum leak may be causing it. Fix that first and clear the codes.
The connector for the O2 sensors and the crank position sensor are on the right side of the intake manifold, there are 3 color coded 4-pin connectors. O2 #1 is the black one.
For the P0327 make sure you have the correct NGK resistor spark plugs in and that they are gapped right. Check for corrosion or green oxidation in the connector going into the DI cassette.
(Former) Saab Tech / Competition Prep