raymarine sd40 to replace datamarine depth

[silentfaith]

i cannot find a old thread on what i want to do....i have a old working datamarine depth corthinian 200? but it is dim to read...i have 2 e80s and a raymarine auto pilot so i want to remove the datamarine and put in a working raymarine st40 depth in it's place.. the old transducer is 200khrz and i hear that the st40 will work fine with that. question...how do i plug in the end to the transducer into the back of the st40? also should i somehow wire it into the e80s or can i leave the st40 depth by itself as all it needs is power? if i can get positive info here i will call my raymarine electronics guys to do this work. hoping it is easy peasy to do.
kindly, craig at silentfaith1@gmail.com