Well that went well...
I'm continuing to strive to make parts that are incredible in every measure: beautiful, light, strong, and most importantly, something that I would put on my own car. I don't mind saying that this decklid is all of those things. I literally laughed out loud when I popped it out of the mold and I saw how great it looked and how light, stiff, and strong it is.
This is a rough weighing of both pieces without hardware and adhesive. I do have a target weight that is a tiny bit lower than this, but I'm confident I will get the necessary grams shaved off in time. It's possible that I overshot the "strength" goalpost... (keep reading

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Did I mention strong?
It passes the jackass test
The test setup. You can see the marks on the inside of the decklid skin where the blocks bore my fairly considerable downforce: