G&G Receiver change

[Left-Ear]

Is it possible to change the upper and lower on a G&G SRXL? im looking at getting this - http://www.fire-support.co.uk/product/madbull-lancer-metal-body-ver2-with-self-retaining-pins-and-shortened-stock-tube

[ak2m4]

I've not changed one myself but it should be possible, however there's no guarantee that the Madbull will fit without some modification - just one of those things with after-market parts and so many different vendors on the market.