I don't have solid info on any of this, but there are no active components on the filter board so it should be possible to make one boot without it. You'd have to reverse-engineer the connectors on all the boards though, which would suck (and if you get one thing wrong you'd fry it).
The board is not the same as Model 2. I believe it is the same across steppings of Model 3.
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Re: Model-3 interface board & stepping compatibility?
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