May not be helpful - but on larger items I tend to use a water soluble degreaser soak and then a wire brushing. In some cases where rust is an issue a soak afterwards in Evapo-Rust. I'll also used water blasting from garden hose and/or power washer - and that will help knock a lot of stuff off the part.
Using this method you would simply use a large tote to hold the soaking fluids.
Here's a 45 gallon tub I use. In this situation it was for a motorcycle tank. Sucker is 30" long so needed something big!
The exterior was fine - it was the interior that needed help. I filled her with Evapo-Rust and let it soak for a few days. The tub was to contain anything that may have leaked out. Hate to lose any Evapo-Rust because it's not cheap!
