I currently have a 1988 Wellcraft cc on my trailer. The tongue [don't know what the main bar is called] of the trailer can be extended {pulled out from a sleve] and rebolted. The crank arm is bolted on, so it can be moved also. It will extend almost 4ft. Single axel, seemes to be heavy suspension. What would the largest cc boat to fit? Is the back of the boat supposed to fit about 8in. from the back rollers? Or hang off the end of the trailor more? The trailer is a "shorelander"