Folks,

this is a type 4 engine ('75 fuel injected). To replace the stock oil
pressure switch with the bulkier sender for an oil pressure gauge, VDO
sells a foot-long flexible adaptor hose for a more remote installation of
the sender. For access to the hole in the engine block, there is a hole in
the tin just above, in front (FIF) of the distributor. 

Question: what kind of tool would you use the tighten the adaptor hose to
the engine block? I can't fit any wrench into the access hole. I'm
thinking about taking a long pipe, pound one end into a more rectangular
shape the width of the nut that needs to be tightened (9/16), slip it over
the hose, and then turning it with a vice-grip. Alternatively, I could
remove the tin, but that's a lot of work. There *should* be a simpler
solution... 

TIA for any suggestions,

Sami