The Märklin catenary system is FULLY functional. It has a pretty complete accessory list, so you can do a full layour very prototipically. (German style)
For running digital it is not really advised, though. Firstly it is not necessary that it be fully functional, and secondary it is slightly less stable for conducting power and data to the locos. It is certainly extremly fragile, should minor accidents happen.
Therefore many ppl choose to install the Viessmann equivalent of the system. Almost same looks and components, but cheaper and can be left without function, for looks only. Then you can also save on installations in tunnels and covered areas. All-in-all less gray hairs! ;-)

WHY do you need to make it functional?

I was just hoping to utilize the Pantagraphs on the locos but I'll be looking into the TRIX so that I can keep all of my logos and not switching to a separate AC system.

Perhaps I am missing something, but why do you need to change your track to add catenary? The catenary power supply will be independent of the track power supply.

Since you say you are using Digitrax I assume you have an existing 2 rail layout to which you now want to add an AC based catenary for either AC or digital control. The biggest concern with that approach is a short circuit between the 2 systems during a derailment, etc.

If you are building new layout and want to add cantenary AND you already have 3 contact Märklin locomotives (AC/Digital) then I'd install the full Märklin 3 conductor tracks even if you were going to run cantenary - that way you could at some point, run a non-electric diesel on the same line and still have the full 3-conductor capabilities. If your all DC then of course that isn't relevant.

If you want to do this for cosmetic reasons, the cheaper solutions mentioned are a good solution. There isn't a need to actually pull the electrical signal/power form the overhead if you already do so reliably from the track/rails.