Brad
I use Koala Degreaser which I found at Supercheap Auto. It is lye based so you need to use gloves.
what I do is put 4 litres in a plastic toy box and immerse the model. Leave sit for about 1 hour and then remove. Most of the paint just falls off and any stubborn areas can be given a gentle scrub with an OLD toothbrush.
This has worked on Tamiya acrylics and enamels as well as Humbrol enamels. I found that the MM Acryls were very stubborn with this and required a lot of scrubbing.
It has no effect on the plastic - even clear parts, and does not effect plastic glued joints. It does eat out PVC (white) glue so canopies will fall off. I don't know what effect it has on CA glue - so PE parts may come loose.
When it is all done I decant the degreaser from the container back into its bottle - just leaving the paint sludge to be tossed and about 90% of the degreaser clean and waiting for its next use.
Brian