More clutch clearance issues

Does it ever end! Decided to fit the clutch slave cylinder now that someone explained which way round it goes (oops!) and I was met with the following:

I can just about squash my little finger in the gap. Obviously this is bad. I've seen solutions on the forum of chamfering the corner off the chassis but that sounds extremely drastic to me. Local makers-of-metal things Mackays in Cambridge may have a job to do for me, namely a bracket that raises the slave cylinder by 10mm or so. The slave also needs to move out 5mm as its jammed up against the oil filter. It's a good job I'm not fitting the oil cooler immediately as the sandwich plate on the oil filter won't fit with the slave cylinder there. What a mess!