Didn't get a chance to have another go at this this evening.
However, plan so far is;
1. I would drill the bolts if I can find some way to stop them spinning around. Only alternative I can see is to grind them off (keep stopping to let them cool down - maybe use a bit of oil/ grease?) but I think that will be a slow job and a good way to ruin a plastic spoiler.
2. Move the spoiler out of harms way
3. Grind off the bottom of the bolt which will be sticking out a couple of mm and also the lip of the riv nut taking care not to grind the holes or make them any bigger (don't think drilling the rivnut out is an option as they just spin round - unless I can superglue them in place temporarily)
4. Knock the rest of the rivnut into the cross member
5. Either put up with horrendous rattling and/or fish the bits out with a magnet if I can find a hole big enough and/or fill the thing with expanding foam
(there must be a better way than this)
6. Borrow a rivnut tool and replace with
stainless bolts, washers and rivnuts (try
http://www.polished-stainless.com - Michael is a very helpful bloke and has all of these and lots more in stock). He also has Rawl nuts which are a rubber version of a rivnut with a brass insert which don't require a special tool to fit. The process of tightening the nut squishes the rubber body. Need to check that they are man enough for the job though - but will be easier to get out if things go breasticles up I bet.
Any better ideas?
