Milano overheating

[Alfisto@domain.elided]

Although my 2.5 V6 rarely overheats it certainly goes way up in 100+  degree 
ambient temperature. Now, however when it goes over the standard 175 degree 
mark to about 180 or so, the oil pressure goes waaaaay down. Does this 
signify that the 20-50W oil is thinning out due to high radiator temp. or is 
the car ready for a new oil sending unit? If the latter, is that the gizmo 
way down behind the head next to the firewall?. How does one remove it?
Graham Arlen.

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