Adding a progressive to a S+ whether you use a Mikohn Cham II+ or buy the rest of the Spectrum parts if any one has them.
You are going to have to learn about how to navigate the S+ Menu's when the set chip is in place.
Program Summery Report (PSR) is going be needed for your your particular game (SP) chip and set chip
The Spectrum is not as fancy as the Cham II+, Spectrum can only show the progressive amount and nothing more.
The Spectrum settings are totally controlled by the S+. you set 4 amounts known as the progressive start or base amount, max amount, current amount, and a increment percentage
The Cham II+ or stamd alone is a actually a stand lone progressive controller and driver for its matching display.
Like the one you show mounted in the player tracking plate.
It will allow you to have a progressive and messages show on the display, The reason you need a computer etc as l listed in my prior post
It will give you more flexibility but you have to have a bit of patience gettiing things up and running.
The S+ would be configured for link progressive.
I, Jay and others have done S+ to Cham II+ setups and some are outlined in the
NLG Archives S+ and Cham II+