you need to undo the baeam plates mate

1 x19mm bolt and 2x 17mm bolts

but still a pain to get out be slightly easier

be careful when you undo the 17mm bolts though

if they go tight do them back up and keep doing this until the bolt comes out as by doing this it gets rid of the crap in the thread

but still be carefull as last thing you want is for a captive to snap in there as its a fairly big job to undo them then