agillings, have you weighed your truck or trailer? I would start by finding out what the actual payload capacity of your truck is and what the actual tongue weight of the trailer is. I would not order new spring bars until you know what the actual tongue weight is. Going to a scale gives you a lot of useful info. and possibly some surprises.
I have to wonder if your TV may undersized for your trailer? The info. I found says that your trailer has a dry weight of about 7,000 lbs, but I could be wrong. Actual loaded weight including any factory options, *could* be in the range of 8,000 - 8,500 lbs. If the tongue weight is in the usual/recommended range of 10-15% of the trailer weight, you could be looking at up to 1200 lbs or more of actual tongue weight. Your trucks's actual payload capacity and the trailer's actual tongue weight is something I'd want to know. You might check the max. allowable tongue wt. on your hitch receiver. I believe it's typically 10% of the max. tow capacity. If your actual tongue wt. is as high as it could be as I outlined above, you *could* exceed the rating.
If your TV is indeed undersized, no amount of hitch adjustment will make it right. I also question why you would use air bags. If your TV sags too much because it can't handle the tongue weight, using air bags won't make it right or safe. If you want the air bags for other reasons, that's different. Just MHO....
I can tell you from first hand experience, having the correct spring bar rating sure makes a BIG difference. You'll never get the WDH set up right if they are too small.