@JadianRadiator 

I recommend you search on Youtube for videos showing how to do antenna mods on Wi-Fi routers.

Be warned that the router could be damaged beyond repair by performing such modifications!

Here is a short summary of the process:
First you will need to purchase four pieces of so-called "pigtail" cables that have through-hole style SMA connectors on one end. It is important to get the correct type of SMA connectors that fit together with the antennas you intend to use. The other end of the antenna cables will either have U.FL / I-PEX MHF connectors that plug into sockets on the main PCB or they might be soldered directly to the PCB. (Might even be mixed, like two cables soldered and two cables with U.FL / I-PEX MHF connectors. You'd have to check this yourself on your C50 V5.)
Next you will have to remove the original antennas and figure out the best way to mount the SMA connectors to the housing of the router. Apparently the C50 V5 is one of the models that have two physical antenna poles. If you carefully remove excess plastic material from the holes where the original antennas were mounted in, then you could perhaps re-use those holes for mounting two of the SMA connectors. For the remaining two SMA connectors you would have to drill additional holes in the housing at suitable locations.
Once all the SMA connectors are installed you plug the other end of the pigtail cables to the small sockets on the PCB or, in case it's the solder-style connection, solder the pigtail cables to the solder points on the PCB (make sure you don't mix up shield and inner core wire).
Then assemble the housing back together and connect you external antennas.

Then the antenna's aren't actually swapable.

As that would make the antennas as swapable as a capacitor that's properly attached to a circuit board... which isn't swapable.

@JadianRadiator 

That's correct.

Actually, home Wi-Fi routers with easily detachable/swappable antennas have become very rare nowadays.