waxoyl...

Hussein,
I will take some pictures tomorrow.
Reason why waxoyl in particular is that it is proven and in that case there is no need to re-invent the wheel. I particularly like the fact that it creeps by itself. Means it gets literally everywhere; will even creep into panel seams. Another reason is the price and availability for future re-application if needed. The creeping quality also means that you don't need to prepare any surfaces, ie removing old rust. It just gets in there and stops it. used it for years now and never ever seen rust reappear where this has been applied. 8) Of course, you'd have to get rid of mudcakes and that sort of thing.
Moneywise, it cost about £70 in materials, but that included the high-pressure sprayer and probe. Time depends on how well you want to do it. Give yourself half a day and that'll leave plenty of time for a few cups of tea inbetween.
The job itself is actually very very easy. Best to do on a hot summers day. You can heat it in winter but the bodywork is still cold so it solidifies as soon as it touches metal, which is not really what you want. Unless of course you have a heated garage/workshop, but then you wouldn't want to do this there. Best somewhere on open ground as you get a fair bit of overspray. On your driveway, it will look like you've tried to lay some tarmac :roll:
Start by opening all dors and bonnet and taking off all the door trims. on the side doors, roll up the windows. Remove the little "spoilers" at the rear side tops where the air outlets are. Lift the carpets and prop them up with anything so that they are maybe 2 or 3 inches off the floor. Also undo the rear lights and anywhere where you'd like it to get into. Coming summer I'll drill a few small holes in closed sections, get the waxoyl in there and fit little grommets to close them off again.
Now get a dustmask, goggles, woolly hat and overalls. Even better instead of the goggles to have one of those safety face shields you use when operating a strimmer or chainsaw. Screw the pressuriser onto the can, pump it up until the pressure release valve starts hissing and start spraying(clear) everywhere into every little nook and cranny you can find. Every now and then you have to re-pressurize the can. I may well use compressor and engine cleaning gun next time... Once done with the upper part, change to the underside with the black and just COAT it - EVERYWHERE. Is quite fun in a weird sort of way. Expect to get very dirty though.
Like I said above, it is best to do it on the hottest day of the year because whatever wants to run off or drip down will do it then. Once done, put everything back together and hey presto - one rust proof G-wagen! :D

Good stuff - will remember next time I need to paint something, though underbody I am waxoyling everything. But good to know anyway, as waxoyl is not to everyone's taste.