Here's all I did to revert back to V3, the rest to get the modified V4 is very easy now since we have an official recovery:
1. Download the LG Drivers (
Download the latest version of LG G3 USB drivers for all variants | AndroMods)
2. Download the .tot (
https://mega.co.nz/#!lAImESRI!fzpKjwS5n0cV73BMkUQNLAUk73xE6lmcc4UmeaDdorE)
3. Download LG Flash Tool/DLL (
https://mega.co.nz/#!QdJA2RxK!iLmXWf0LXqbxsUtD6vNmnhhR4pTfJTW2Np3HWE2_hQo)
4. Download the megalock.dll (
https://drive.google.com/open?id=0B2HGbpXvpDInLWFNd0tBX2hqN0U&authuser=0) put it where you installed Lg Flash Tool (ex. [C:\LG\LGFlashTool])
5. Launch LG Flash Tool, select option 3 if it asks. Select "Manually select DLL". Find "LGLS740_20140414_LGFLASHv160.dll" that should have been in the LG Flash Tool zip. Then click Add and find "LS740ZV3_17.33030_Secure.tot" which should be in the huge 1gb zip you downloaded. Then be sure to select Board_DL and press OK.
6. Turn off phone, plug one end into the phone and the other end into your USB. Press and hold Vol. Up until the DL screen appears.
7. Go to Control Panel on your PC, go to Device Manager, find Ports, find the one that has LG in it or anything identical. Double click and go to the Ports tab, click Advanced and change Port to COM41, if in use just hit Ok anyway.
8. Go back to LG Flash Tool, click the big "Play" like arrow button. It will say READY above COM41. Hold power until you see nothing but a black screen, immediately press and hold Vol. Up, keep holding until it starts flashing the file.
9. When it boots into Mini OS, touch Ok and hold Power and touch Normal boot.
10. Now you're back into V3, you're welcome. Now Update you PRL and you're good to re-root and flash the recovery and the modded V4! This is the beginning to something big.