I pretty much used this guy's design.

https://www.youtube.com/watch?v=enymJGPbtf4

Here are some of my iron relics after electrolysis. Wish I had "before" pics. Some relics like that horse were barely recognizable. I use sections of rebar for the sacrificial anode and 2 tablespoons of baking soda per gallon of water. One very good tip I picked up from Aquachigger's video was to drill a hole into your large iron relics and insert a screw, then attach the alligator clip to the screw. Much better and faster results that way because you have a good connection. My charger has 3 settings. I usually use the highest (6 amp, 12 volt). Needless to say, you need to keep your head in the game and do things safely. Depending on the size of the relic and the amount of rust, it usually takes 2 to 5 days. I'll stop it once or twice to brush off loose rust and reposition the relic.