Itīs easy all is connect to the PLC. If you want more help send to me your electric diagrams by mail and I could tell better what you have to do, I usually do retrofitings and always try to use the original wiring. Oviusly the original wiring must be good.
Enter
www.fagorautomation.com and download the manuals. You have also the 8055T itīs a little expensive than the 8035 but it has a conversational programing inclued for machining. Itīs very usefull.
Carlos Cabrera