It sure sounds like it to me.
Have you heard about CPP's 500 series box? It completely eliminates the slave cylinder and is a direct bolt in with no frame modifications required.
The boxes they sell are new boxes and not rebuilt like most (if not all) the ones you will find at the parts stores. It's about three times the price but well worth it imho.
I'm not sure what the original ratio was but the 605 box is 12.7:1 and the 500 is 14:1