Replace bonnet release cables

Can anyone help I have 2 seized cables and broken release handle. I have bought new cables and handle.. Need to replace the cables but not sure the best way can't get my hand in there under bonnet has anyone ever done this change Do I Need to take radiator expansion tank out to get to where the cables go through the bulkhead .....any help would be good. Thanks

Done it now.. Bit of a pain to do single handed