I've been on the (fab) S Series website, however, it doesn't tell me what the torque settings are for the Rocker cover bolts on a 2.9 V6 engine (1991 S3).
However, if you are using Motorcraft gaskets with the steel spacer pins fitted, it's easy to tell by feel when the gap closes on the pins, and stop there.
If you use the recommended torque settings with an ordinary cork gasket, you'll squeeze the gasket out of the joint and it'll leak like a government department during a civil service pay dispute.