Later this afternoon, I got the L-brackets installed for the monitor shelf... I also followed Saint's book advice and drilled from the outside cab sides into the support braces and put in a substantial amount of screws to keep those braces from falling... and the monitor.
Monitor is installed, but...
1. Speaker shelf is too long... will need to trim it quite a bit.
2. The monitor needs to be angled upwards a little... will need to experiment with placing some scraps wood underneath the front of it.