VFC Gearbox Compatibility

[R.T Plissken]

I have a VFC MK12 lower that needs to be replaced and I've done my research to know that there are no compatible lowers for uppers or vice-versa. My next course of action (before having to purchase a second rifle...) is to replace the entire body. My hesitation is that even after speaking to a retailer over the phone he was unsure if a VFC gearbox would drop into a G&P metal body without any major issues.

Does anyone have any first hand experience with this?

Thank you!