Chances are, you may have had an old version of the VL-3 915 mod. There are a lot of old versions of it floating around various sites online. That’s likely why you also got the pre-packaged G3X without realizing it. Make sure you’re downloading the most current version (0.31 from Jan 2) at the link below.
Also, make sure you don’t just update the 3 WT mods. DELETE the folders from your Community folder completely before installing the new versions. The old versions may leave some files behind that cause issues with the latest versions.
On a side note, that VL-3 mod is awesome. It made that plane my #1 choice for sightseeing tours. It can do low and slow with great control, and when you hit the power, it goes like a scalded cat - something the stock plane was sorely missing.