ah yes mate,
i remember, it was a bit of a job to get it in but you just ned a punch or srewdriver and tap/ bash the pin out.
once you have started it off you can use the pin from the tck trigger to tap the rest out
but be carefull not to luse the two spacers or washers either side of the cp trigger
hope this helps
soul snatcher24
if you have any problems feel free to pm me