CaptainMacHaddish I'm pretty sure there's a version of ABH that doesn't use as much RAM, because it just adds the parts instead of adding all the other ship types. That's probably the first place to look, otherwise you may want to manually comment out un-needed parts, like so.
// <example_part/example_part.txt>/Part
There are other, similar things you could do, but they require a little bit of Modding knowledge to accomplish.