hi mate.what do you mean best place to fit them?mechanical gauges or electrical?i guess with you saying diagram.electrical.if so.you can get a oil pressure sender from nomad racing and it replaces your original and still alows you to have the oil light.as for temp sensor.they also do a bung that goes in the sump.as for lighting the gauge up.take a feed from your side lights and an earth.job done.hope this helps atall