Here's my version of a tripod mount for the I2. All the components come from berkeysystem dot com, except for the tube clamps and the universal mount plate, which came from Amazon. The tube clamp design allows a lot of flexibility in I2 configuration. For example, it can be rigged to allow take-off directly from the tripod mount.

Do you lock down the gimbal too? I guess pointless with the I2 mounted to a tripod?

No reason to lock down the gimbal. The base isn't always a tripod, anyway. Sometimes it's a moving base. For example, it really smooths out dolly shots, especially when the dolly isn't on a dedicated track.