Official NZBGET Install While Stopping current installed version

I currently have the WD “version” of NZBGET installed on my NAS, since there is no longer an upgrade via the upgrade interface on the WD itself…can I stop this WD version and install the official version, currently 21, from NZBGET in a different location other than mnt/HD/HD_a2/Nas_Prog/nzbget .perhaps in Nas_Prog/myprog

If this can be done, I assume they will not both run at once…if one is started and the 2nd is attempted I assume it will give an already started message…anyone?

thanks