Question w/ recording vocals? signal levels?

Plugins, eq, compression, etc do NOTHING to the recorded waveform, only the monitored playback. TO prevernt converter overlead you MUST use a hardware compressor before the A-D converter. For the 001 and M-box, nominal(average) recording levels should be targeted to -18dbfs. For the 002/002R -14dbfs.

Question for where and tele: If you don't own a hardware compressor - couldn't you set up an aux track, add the compressor as an insert and then bus that to an audio track to record?

You could, and many do, however this will not give you any headroom before the converter, which is where you need it.