Proper tongue weight
David, You're probably going to have to go by a trial by error procedure to find the proper tongue weight for your trailer. In other words; you're going to have to get the center of the keel directly over the tandem axles and use a scale to get the 10% of the boat's total weight on your trailer's draw bar. I don't know how you are planning on doing it. For instance, whether you plan on having it set on the trailer with a lift, or putting it on from the water, but we're only talking a matter of a few inches forward or backward on the trailer to get the proper tongue weight for the ball of the towing vehicle. You don't want too much weight in the back of the trailer, or it will fish tail while being towed. So, it's really a matter of getting the boat on over the axles, checking the weight with a scale while the tongue is in a horizontal position and not connected to the towing vehicle. Once you get the proper tongue weight, you can move your winch stanchion right up the bow and tighten down the bolts. Then you can get the proper adjustment on your bunks with two Hydraulic jacks and a little measuring to get both sides equal. When I set up my new Long Mfg. trailer for my boat, I used four of my sailboat stands in the stern of my boat, two on each side, to do it safely on land. Good luck.Joe