Here's a video on YouTube where a guy made some inexpensive spring loaded tie downs with chain, springs, and U bolts. If the link below doesn't work his channel is called Northern Explorer Overland.
https://www.youtube.com/watch?v=XhkU3IPcIz0
I hauled mine home with a chain and binder and ratchet strap combo. I scariest thing I've heard of is if the camper tries to hop/rise up off the truck bed when you go over a bump in the road or when your truck bed flexes you could damage your anchor points on the camper. The screws or bolts could rip out of the wood frame. That being said, I suppose it's possible to over-tighten the turnbuckle style tie downs and have this happen also.
Nothing wrong with being creative, but be cautious as well. Here's what I came up with for my flatbed setup. Way cheaper than the frame mounted setup, but I did purchase the spring loaded turnbuckles.
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