Ute, Canopy over a deck liner.

Who has done this? i bought a nice second hand Courier that had a deck liner, but no canopy. I later bought a canopy for the back. Bugger! no access to the nuts when drilling and bolting the canopy on. Nobody had 10mm rivnuts in my town. I ended up placing the (pre-drilled) canopy over the deck liner and marked the hole positions on the flange, removed the canopy, drilled through the deck liner and the deck flange, then removed the liner and had to figure out what next!

I have a mig welder but wasnt confident enough to reach up under the flange of the deck and weld a nut in without risking damaging the paintwork or something.

I ended up welding 'wings' on the nuts so they wouldnt spin around in the confined space up under the flange and hot gluing them in place with the bolts fitted to hold them until the glue set.

I put a bead of sealant around the perimeter where the canopy would sit and fitted the canopy into place and bolted it down.

This has worked well but seems like an awful lot of buggering around for an otherwise simple fit.

How would the pros have done it?

You pretty much have to cut access holes in the liner to get at nuts. Or you cut the lip off of the liner and just screw it in place. And once on don't forget to re tighten every so often.

I wasnt keen on cutting holes in a nice deckliner.

Other than rivnuts, are there any other captive nut systems that would work?

I could suggest a long convoluted idea but i'm not sure how it would come across on here lol.
Basicly, put bolt head under lip secured to a plate, or weld a threaded rod to a plate, then rivit the plate to the lip of the deck, place liner back over the top of threaded rods then canopy on, tighten nuts etc.

I have mine held down with tie- downs, (on the inside !) so I can take it off or put it on as needed. I just hook on a cable and winch it off into the garage ceiling. A one-man operation and under 10 minutes to do.

The problem with rivnuts in this case, is they would tend to pull up into the plastic, and they would lose their grip and most probably spin if needing to be undone.
If it was insurance and we got stuff-all as usual to remove the canopy - they would spin!

What you did OP was a good idea.
Most are done in a similar fashion, but in reverse.
ie, a short plate with a nut welded on. After drilling the holes, bolt that under the deck hole, and fix it in place with a pop rivet each side. Remove the bolts - place the liner back in, and plonk the can'o'pee in place.

That way you only have a bolt head showing instead of a stud & nut.

Six to one - half a doz to another.

normally you get a under lip deck liner for that exact reason the over lips are designed for hardlids and the like

That makes sense if it is being done from new, but not practical/cost effective for a retro fitted canopy.