Cool. A T-120 was the first sit on top I ever fished from.
If you are just using traps, there really isn't anything special you need. The biggest ordeal will be utilizing your space to haul your gear. We've done traps before by stacking them in the rear tank well. My buddy and I have done 10 each, with a container of some sort bungeed in front of us to hold the crabs. When doing this, you just have to get comfortable with shifting your weight around...and just know your kayak's limits with regards to stability.
I now run a trotline from my kayak. I have a Torque, by Ocean Kayak, which is powered by a trolling motor. Being truly hands-free makes it easily capable of running the trotline. A buddy of mine also runs a trotline from his Hobie, driven by the Mirage drive (foot pedals). The key is being hands free, as you need to actively use your arms to dip.
Using traps can be effective. Like if you find that the most traps you can safely carry is 7....just make a couple of trips from shore. Odds are that you wont be crabbing too far from the launch regardless.
I started late in the season last year. This was my video from my first time out with the trotline.
http://youtu.be/7P9MCz_XJNoMy second time out wasn't as successful, but I'm not afraid to fess up to a bad trip
http://youtu.be/KL4VoZ44l5wI am getting ready to give it a go again this season. You are mroe than welcome to join me and the rest of the kayak crew!