I moved from a MG to a MK Terrova IP last fall on a 04 PT 175.
You may/may not have to swap out the plug recepticle for the TM, it depends on IF you use the one from your MG or a new one just like what is on your MG now. I just bought a new plug for the MK to fit the recepticle on the boat. Easier imo.
Your SR set up may/may not have to be moved, it really will depend on "where" you mount the MK. You will probably have to move your SR rig as the MK deploys differently than the MG. It slides hortizontally down the mounting bracket, and the HU will hit the SR rig. The MK mounting base will stick out past the leading edge of your boat to allow the shaft to be vertical when deployed, and the HU may stick out more to outside of your boat since you have the black "cap" on the very front of the boat. I mounted my MK directly to the front deck material, and had to drill some new holes in order to mount it securly. Some have used the MK mounting brackets and some have made their own. I did neither, I just mounted that sucker to the deck, its a solid mount too but does stick out past the leading edge of my boat.
I would lay a good layer of masking tape over the front of you boat, then set the new MK on the bow, have a buddy hold it in place/different positions and see what's going to work for you while you are in the boat. Go thru all the motions of launching the boat (the TM base may hit the front roller/winch bracket depending where you mount it), deploying the TM, everything you would do on a day fishing. I used a 1" long socket to get my 1" clearance between the shaft and leading edge of the boat for consistency.
It looks like you have a Lowrance on the bow, that means the TD cable/wire will have to be flopping around to keep the wire from being damaged when the TM spins over 360*. You'll have to get a bit creative on securing the wire to avoid damage, look in the IP thread and you might see some ideas, or google it and you'll get some more ideas. I had a Low on the bow, did not like the wire flopping around, so I got a HB for the front since the TD wire will fit in the "slot" on the MK shaft where as the Low TD wire will NOT fit in the slot and allow the MK to deploy.
GO BIG ORANGE !
I meant to behave, but there were just way too many other options available at the time.