Oil sending unit/switch

O.K., from the specs on the sending unit link that you provided I'd guess that you need a male 3/8" 18 npt to female 1/8" 27 npt reducer fitting.


If you wish to retain the ability to use your stock warning light as well as the meter, I'd recommend a "street T" with a 3/8" male npt to two female 3/8" npt outlets (see attached photo). This may also serve to provide you with some working distance from the oil pump/filer holder assy if the sender is too pudgy to fit in close.

You can then put the stock switch into one section of the tee (if the thing survives the ordeal to remove it) or plug the extra hole for future use.