If you have hands the size of a 8 year old Chinese electronics worker maybe, otherwise prepare to drop the tank and get super dirty doing so.
The upside is if you run it empty its fairly easy once you break through the rust and years of muck and dirt/grease... I'd prepare to replace the straps and bolts/nuts though, and then take the brackets off and give them a good cleaning/de-rusting.
A good power sprayer and set of goggles and ear plugs (two sets, one to keep crap out of your ears and another to keep stuff from going up your nose as you lay under the truck) will be a useful start, and then after that PB blaster and a can of that freeze-off to use on the strap nuts will help as well.
