Length of tailgate chains

Are the tailgate chains on an M715 supposed to be long enough to support the tailgate in a flat position (level with the bed floor) or are they just there to keep the hook from getting lost?

I have no chains on mine and I am going to go to Lowes and buy the stuff to make some. I am not interested in originality, just function. Any idea how long these are supposed to be? Also what size (diameter) chain should be used?

Thanks.

Bob

Mine are long enough to support the bed in a flat position and the links are about 3/16" in dia. Hope this helps
Redneck1

I bought a new set from ABLinn. They aren't installed yet so I can only hope they're right.

Anyhow, from the inside of the hook to the inside of the last chain link is 20-1/2". From there you need a way to attach the chain to the truck - I believe stock uses one of those split chain links so that'll and another inch or so to the length.

Chris

Thanks