You are in for some fun Midas. We just finished up doing a double Brutus build in my shop. We used 16 gauge Stainless Steel, where Lonnie used 11 gauge, 16 is fine IMO. I used impinged jet burners and Ubermick did Banjo burners, we haven't done a boil off to see which is faster yet.
The gas beam was living hell for us to get it to stop leaking. My advice is to have it welded 'preferably TIG' and sealed at both ends then pressure tested. Only then, carefully weld it into the frame.
Allow WAAAYYY more time than you think it will take. I still scratch my head and wonder at people who say they build it in a weekend. They must be much more skilled than I.
We used the double display Auber PID controllers. It's nice to have your set temperature on display with the actual temperature. They have a dumb down mode where they operate like Love controllers, if that's what you want. They are similar in price to single display Loves. I haven't tweaked the parameters completely yet, but I think the PID will be superior at hitting and holding temps. I'll post a thread on my results when I'm done.
If you have any specific questions, let us know and we'll try to answer from our experience.