One set that I found was located in the location /system/media and the following files I found were:
Meanwhile the second set was located at /carrier/cust with two sub folders labeled poweron and poweroff, each containing their own files:
After replacing both sets of files a reboot confirmed that the boot animations were successfully replaced! As of this post I am unsure if the first set of files needs to be replaces as well or if the ones in /carrier/cust only need to be replaced, I am assuming that since it didn't reflect the first time with only the first set replaced that the second set is all that needs to be changed. I can confirm that this works on the LS990 but I am insure of any other models, so try it and report back if it worked for you. Since your modifying system files you will need to have root (StumpRoot for Sprint users).
~LGG3 via Chrome