Welcome aboard Dougie, I would gently prise on the rear exhaust till the glue gives away ( or the plastic breaks but then you deal with that ). There are 2 camps on the airsoft guns here, I am in the one that rarely if ever uses them and convert most of my tanks to infrared combat. The other camp would contain people like Swathdiver and Perry who fine tune there guns and blow things to bits. Lots to be learned here from both camps. Its tradition here to post pics of your projects so we can enjoy the full scope of your efforts. On a side note I met some Scotsmen this weekend and boy can they drink and have a good time