I have searched for 2 days and cannot find an answer to this.  How do I change multiple MIDI events so that the MBT align with the beat. For example:
Eb   01:01:123
Eb   02:01:563
 
I want to select all the Eb notes and change them to have their 'ticks' set to 000. So they align tight with the beat.
 
Any help appreciated.

How about this.  In PRV, select the notes you want.  Then Process->Quantize and select whole notes.

You can clikc a key in the PRV keyboar to select all Eb event, but if you only want to get the ones on the first beat of each measure, start by selecting the whole clip, then Edit > Select by Filter and specify note and beat and OK to narrow the selection. Then quantize as tparker suggested.

The Process -> Quantize function will do it, mostly. The problem might be what do you want to happen with 02:01:563. Quantizing will move it to 02:02:000, because :563 is closer to beat 2. (Unless as tparker says you want everything at beat 1.)
First, select all the Eb. You can do that in the piano roll by clicking the Eb key on the keyboard to the left. If you have multiple octaves of Eb, ctrl-click the others. Or you can use the more complicated Edit select filter.
Next, open the quantize dialog. Set resolution to quarter note. That will set the ticks to zero.
 
If you truly need 01:563 to go to 01:000, you'll need an extra step to nudge all those notes earlier by :959 - :480 = :479 ticks before doing the quantize. That's because quantize sets all notes between :481 of the previous beat and :480 of the current beat to :000 of the current beat.