The upgrade went very well. The adapters are reasonably priced and Galil shipped quickly. I initially thought the adapters would plug into the cards and my old DMC-1050 cables would plug into the adapters. However, this is not the case. I still needed the newer cables (cable-100-m) intended for the DMC-1880. Hardware route is as follows; DMC-1880 -> Cable-100-M -> CB-1500-10 -> Older 60 pin cables -> ICM-1100.
The machine was already wired to the ICM-1100's, going this route allowed me to upgrade to a PCI board, Newer computer, Operating System (WinXP), and Mach3 with Galil plugin using G-code without manual conversion, without rewiring. If I could have found the ICM-1900's for a good price adapters would not be need but rewiring would.
The plugin works well so far far; my only issues with it were configuration.
1 Description of Limits in plugin config appear to be backwards from the Galil command set.
2 I was not able to jog off of a limit until I entered ports and pins in the jog entries in setup. (the manual did not mention entering anything for Jog)
Although I achieved the initial objective of using Mach3 with Galil, through the process I got the opportunity to learn a good amount of the Galil command set. I have to say I really like it. It is intuitive and organized. I wish there was an affordable front end (GUI) that takes the place of Mach3. It would be a bit cleaner in implementation and operation. As I understand, Camsoft is it but nowhere affordable in my opinion.