I have one of the machine mart blast pots which if combined with a big enough compressor is great for small items but would take MONTHS to do a whole vehicle...get a professional in then it will be done in two days!
You can use blasting on cvrts - I had my Spartan done earlier this year but you need to be careful and it is VERY messy, despite best efforts it took for ever to get crap out of all the nooks and crannies. I have also seen a very nice Sabre which years after sandblasting still makes horrible grinding noises when turning the turret! Following Jon Pentons approach seems to be the most efficient way ie a big rotary wire brush on an angle grinder.
My advice (which isnt necessarily the best I have to say just one angle!) would be to remove whatever you can - decking, bins, smokes etc and have these blasted and primed separately, then block the vehicle up wheels and tracks off and wire brush/ needle gun followed by priming and painting (you need to rejack and move the blocks to get at the covered bits). Then put it all back together and finish it off with a final coat to bring it all together.
Or you could do what the army do and employ an old english sheep dog, cover it in green paint and let it roll around on your vehicle a few times...
Just keep telling yourself it will be worth it when its done...
Cheers
Tim