Squid guard offers a lot of opportunity for creativity, and the techniques you can access can lead you to some very interesting positional opportunities. Here's a good sequence you can use in order to sweep and pass, or get onto your partner's back.
To set the position up, enter into squid guard, and grip your partner's sleeve with your free hand. From here, you can set up a Lapeloplata, or you can move toward the back by dropping your own knee in front of their legs, in between them, and by pulling their knee onto your chest. From here, you can swim your free foot around, grip their pants, and free your other leg in order to take the back.
Your partner will often turn in order to avoid the back take, and this is an excellent opportunity to follow them with a crab ride.
Alternatively, you can hook their hip with your foot during the "Matrix" entry, and grab their pants leg. Use your hook and the grip to bring your partner toward you, sweeping and coming up on top for an "unfair 50/50" leg drag.
Alternatively, you can pass this way, by bringing your far leg all the way to the other side of their body, ending up in knee on stomach.