HELP mk1 golf gti cab metering head needed,

hi guys im new to he dub seen and just got myself my all time favorite car a 1983 mk1 1.8 golf gti cabby,
to start off i had a running problems, after the auto choke switched off she wouldnt tick over unless throttle was applied and then sounded like it had a miss untill you floored the throttle, i could smell fuel coming from the exhaust so after going on a few forums i had a mess with the fuel mixture ( 3mm alan key on the metering head) got it to tick over at 1500 rmp and sounded smooth, not happy with that i had 2 mess again  :redfaced:  and now she starts for 2 seconds then cuts out even with throttle, i think ive broke the metering head ? any ideas or a metering head i can buy from someone would be great thanks D

mess with it some more, adjusting the screw wont damage the metering head but its possible to put the co and idle screws so far out of adjustment the car wont run. been there myself messing about swapping various mh and airflaps about on my 16v

forgot 2 mention that when messing with the fuel mixture screw the last time it unscrewed and fell inside the airbox so i had to strip it and put the screw back in, would this of damaged it ? am i best just getting a new metering head that came of a running car ? instead of messing anymore  

ha ive done that before as well

the important thing is you put it back together properly, its very fiddly to do it right. if not this could explain why its playing up! its almost impossible to do without stripping the air flap down completely