Our neighbour has a very accurate set of scales so we put them on our crane and weighed a couple of things.
1st was a new 5.0 L Mustang engine with no alt/starter or manifolds, it was 198kgs
next was a 2nd hand LS1 with starter/aircon/power steer and manifolds it was 209kgs
then we weighed one of our hulls (RiverPro 440) It was 220kgs