Hello Phil--With your help, I was able to get just what I wanted!
Compressor (FS1) --> Acoustic IR (FS2) -->FX Loop 1-->Optical Trem (FS3) -->Chorus (FS4) -->Reverb (FS5)-->Ext Amp (FS6)
As near as I can tell, this places the Compressor and Acoustic IR before the amp and the Trem, Chorus, and Reverb in the FX loop of the Mesa Amp.
Thank you so very much!