This will handle things, but you will be at limits. 1,500# isn't lots of room to spare. Also remember that the 7 ton rated trailers are including the trailer weight minus tounge weight. so 17000 gross on trailer, you need to place 3000 on the truck. On this size setup I would hands down reccomend a gooseneck. 3000 tounge weight on a tag-along and this small truck will make it too light on front.
I'm not saying you cannot pull a gooseneck with a dump, but you will have to remove the sides or a section of the sides to accomodate the turning radius.
buy the gooseneck and consider updating your whole setup to a "2 ton" truck and tag-along when money allows.
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