Suspending large objects in epoxy river

Hello everyone, new to the forum but not new to resin. All my pours have been river style from 0.5″ to 2.25″ thick; latest pour was a coffee/end table that used 6 gallons. Whenever I try a new technique, I always experiment on something small first (to avoid wasting expensive hardwoods or gallons of epoxy). Which brings me to my next big project I am starting to plan for. It’s my parents anniversary next year and they own a helicopter company. The first helicopter they bought over 10 years ago just had the tail rotors removed from service and I would love to cast them into a dining room table clear epoxy river.

It’s a smaller helicopter (Bell 206) so the tail rotors are ~1″ thick, 5″ wide, and 30″ long each. Unsure on weight, maybe 5lbs each. My question is; what would be the best method to suspend them? I’ve done some research and my options seem to be:

-Do a 1st layer pour, let it half cure, then let the objects (blades in this scenario) “suspend” in the half cured epoxy before pouring the rest. My concern with this is that the blades are tapered and may end up at a strange angle. Also, I’ve never poured clear epoxy, would the line between first and second pour be noticeable?

-Have an overhead stand with fishing line hanging down and holding the blades suspended on their own while I pour. This is preferable as I can do the entire pour at once (thick pour epoxy with cool room and fans, not concerned about the heat). I guess my only concern here is the potential buoyancy of the blades leading them to float.

-Make some kind of recessed base within my form to allow metal rods or sticks with glue to hold the blades in place from below. Not too concerned if you could see the leftover metal rods below the blades after its all said and done.

-With any of the above options, I appreciate that I’d have to thoroughly clean the parts and brush them with epoxy first to avoid any air bubbles.

Any other recommendations? I’ve never casted any objects in epoxy so I’m new to this aspect of the hobby. I plan to practice on a few smaller projects first with the same technique that I will use on this final project (3″ dining table length black walnut, likely 10+ gallons of epoxy, and irreplaceable helicopter parts is not something I want to experiment with). Appreciate any help! Thanks.