P38A Intercooler

Can anyone advise me how you get the bottom drivers fixing bolt out of the intercooler I have taken the other 3 out but cannot see how you get at this bolt to take it out

I changed mine a long while back, but I didn't do it, the ppl (in Gloucestershire way) did it for me, and managed to strip the thread from my rad, I had to stay the night to get another one fixed in, to this day I dont know if the bigger one made any difference or not, just seemed a good idea at the time gives you more cooling and HP dont it??

A while since i had mine off but not difficult if you use a 3/8" socket set and a wobbler as i recall. Bit of a fiddle that is all.