Ron,
Lycoming lists a variety of fittings in the parts catalog:
4,8 is the standard plug.
10 is called "Adapter, oil cooler connection", #71600. The female thread is 3/8 NPT.
18 is called an "Elbow, universal, 75 degrees". The part number is AN777-8D, so I assume the connection is a standard -8 male flare. You would also need 17 (#71623), 19 (#AN901-8A), and 20 (#71620).
9 is called "Connector, acc hsg to oil cooler inlet hose", #69675. A note says "3/8 flared tube connection to oil cooler". Sounds like just the thing for an accumulator.