What's the weight of a bracket- barnyard find

[FishStretcher]

I just bought a bracket off a metal fabricator who was trying to unload his 20'SF project on craigslist. He built a bracket out of 5086 aluminum. 30" setback with swim platform. I have a concern about the weight. I bet it is 120lbs, mostly because it is made out of 1/4 aluminum, and the motor plate is 1/2".

It has a center floatation volume, good for 260 lbs by my calculation, or 130lbs net buoyancy. I will probably add more buoyancy to the sides under the swim platform with some 1/16" boxes for foam.

Anyone know what a raw Hermco or Armstrong weighs? I bet half this.