tongue weight

Ok, to answer a question, I towed this trailer home( about 30 mi.) with a Chevy Tahoe with nothing more then a 2 5/16 " ball on the back of a Tahoe and that's it. This was before I signed on to this forum. Knowing what I know now, that was very dangerous but considering I had no wdh with sway control it towed ok. I definitely won't be doing that again until the proper safety measures are taken. Now after that is said , my Wife and I started looking at trucks not only for the trailer but since I'm in the construction industry and trying to start my own business, we thought a truck would kill two birds with one stone. Before I go any further I want to point out that my trusted mechanic and fellow RV'er looked at the owners manuel for my previous Tahoe and the trailer and told me I could tow it, granted I was totally maxed out but I was within the capacity of my Tahoe. Now I was just at the dealership today to drop off some paperwork for the Silverado that we just purchased and they told me the Silverado was rated to tow 9200 lbs Max. and told me I was looking at the wrong gear ratio. I know I'm new to all of this and I have a lot of learning to do, but I did do some homework before I purchased this truck. I did ask several different credible people before this purchase and everyone assured me that I could tow this tt safely assuming the proper safety measures are taken ( wdh, brake control, etc). I understand towing such a vehicle without those things was very reckless on my part and there was a lot of ignorance in that situation. I have towed things before but never anything this big and I just didn't know about sway and a wdh and so on. But I can tell you I won't be making that mistake again. So back on subject, that is all the info I have at this point and I'm trying to get a proper setup to tow safely. Should I just play it safe and get the biggest made which is 1400/14,000 lbs and know that I'm covered or do I need to get a accurate weight? And I also want to state that any and all help is welcome and appreciated. Thank you.