Sounds like you already have a good picture how you want to set up. Since the ISG(Juniper/Netscreen?) seems to be controlling routing/FW and 80E is just an AP concentrator/aggregator, I would set up CAPWAP tunnel mode from all APs to 80E. Nothing seems to be special with your arrangement.
SSID GUI has operational vlan config box at the bottom. Then you need to create vlan interfaces and attach them under the physical interface for 80E to accept. That part has nothing special because of WiFi. Regular vlan config.
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