thread size for '86 spider oil pressure senders?

["John Dohrmann" <jdohrmann@domain.elided>]

Can anyone tell me what the thread size is for either the oil pressure light
switch or the oil pressure sender for the gauge in my '86 spider (2000
engine)?  I want to get an appropriate adapter to put an aftermarket
mechanical gauge on it to confirm (I hope) that my pressure gauge sender is
the reason my pressure is reading so low.  I just replaced the oil pump last
spring.  AND the idiot light never comes on.  But the gauge doesn't read
anything like it used to.

John D
'86 spider Quad

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