The 26-3024 requires a PAL or GAL replacement. The 26-3124 is upgraded with a cheap IC wired in and a trace cut. The how-to should be available on line. Bruce W. On 03/22/2017 09:13 PM, Bill wrote: > What is the difference between the 26-3024 Coco3 upgrade and the 26-3124 > Coco3 upgrade? > > Thanks. > >