Hi Dave
roofracks something similar to what you describe, are often used here in Australia for 4wds that do genuine outback driving, extra spare wheels and fuel being common, but also small dingy boats with outboard motors etc for fishing buffs and folks who like to get around, in the far North, during the Monsoonal Wet season
Good idea of yours to keep it as low as possible, for 'round town driving/garages etc. However if it's completely removable then that'd save even more on your petrol/diesel fuel costs, when not in use simply take it completely off
The large Aussie ones (available at many many roof-rack and towbar supply and fitting shops) would also, almost always have a small ladder incorporated into them, makes getting up on top w-a-y easier, eh ! So keep this in mind when making your own rack
cheers
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Catherine Jemma.......(Keeper of The Gem of Amara) Outback Western Australia .... snipped-for-privacy@agn.net.au.knickers
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