I was reading a lot on the old forums (lots of good info.) I noticed several questions about rust removal. Some people went as far as cutting fuel tanks to pieces to clean out rust and then weld them back together. I learned from a guy who made a living for many years restoring old cars and tractors for customers how to do this. Just put on phosphoric acid on the rusted part or better yet submerge the peice in it. I saw him put a whole 6 cylinder block in a tank of this acid and he said in a few hours it would come out clean. This block was coated with thick rust inside and out.
This stuff is not even toxic I am not sure where to get large quantities he had a tank with about 80 gallons, we use it all the time for cleaning lime scale of house taps. It is available from any supplier of dairy farm products it is used to clean the pipelines in dairy barns that the milk comes to the tank through. They call it milk scale remover.
Another remedy for cleaning up BAD rust and old paint this same man told me about and I have used very successfully is caustic soda also known as lye or
sodium hydoxide mixed in water. This is more toxic and must be used more carefully you MUST add the powder to the water NOT the water to the powder because of the heat caused. About a cup to 10 gallons of water and soak your peice in it till it comes clean then wash (I pressure wash ) and dry.
I find it simpler than sand blasting. If you doubt this I suggest you try on a peice of junk I am sure it will work for you as it has for me.
D.K. in S.K.