You don't need a tongue scale. Go to a CAT certified scale and do three weights...
1. Drive onto the scale with your truck and trailer. You need to have your WDH. hooked up and engaged just like you would when you are towing/travelling. Front wheels on pad #1, rear wheels on pad#2, and the trailer wheels on pad #3....push the button and tell the operator to take a weight. When complete, go to #2
2. Do not move the truck trailer from original position. Now, completely disengage the WDH spring tension bars. No need to unhook or take anything off, just release all the spring tension. Push the button and tell the operator to do weigh #2. Once complete, you can either hook the WDH back up or you can drive off of the scale. At this time, you need to disconnect the trailer completely from the truck and get a TRUCK ONLY weight.
3. Drive back on the scale and tell the operator that you are ready for weigh #3 (front tires on pad 1, rear tires on pad 2). Once he or she gets weight number three, drive off and hook your trailer back up, including the WDH and spring tension.
Go pay for your weights. Normally the first weight is $11 and each additional weight is $2 each, so you should owe $15. Collect your three scale tickets and head home and put the numbers to work.
Once you are home and have the scale tickets with you, fire up the computer and go to this web site....
http://fifthwheelst.com/
Once the page loads, at the top of the page you will see a title that says "4 Step Weight Safety Plan"....click on it and follow the instructions completely, including doing the worksheet. When you are done, you will know everything about your truck and trailer weights that you could possibly know........except the exact weight of the beer in the fridge!