Bryan: No, new BLMA trucks won't lower the MT car enough - I tried that. It's actually easier to use the Atlas trucks, because they allow the entire circular mounting boss to be removed. With the BLMA one would have to carefully remove just enough of it, while with the Atlas there's no measuring needed.
On the other hand, on my MDC conversions, I used the BLMA trucks and some filing, because it would have been too difficult to remove enough material to use Atlas trucks.