You will have difficulty with your proposal. The Danfos is used to switch two circuits - hot water which supplies power to fire the boiler and central heating which powers the pump usually via a room stat.
The salus can only switch one circuit so will not replace the danfos.
According to the User Manual for the Danfos 103 "Your 103 timeswitch has one time output which can be used to control your heating and hot water at the same times". This is why I bought a single channel programmer to replace it. The wiring diagram in the manual also only shows one output. Have I got the wrong manual for the Danfos?
Yes you are correct I was picturing the rectangular controller with separate settings for ch and hw.
Terminal 2 on the danfoss becomes live when the controller is calling for heat. There may be two wires connected to this terminal.
You should end up with neutral and live on the N and L terminals and the wires to terminal 2 on the danfos should be connected onto terminal 3 of the Salus. Terminals 1, 2 and 4 are unused.