Does anyone have suggestions on fittings that would properly integrate the cooling fan switch and temperature gauge sending probe into the holes drilled into world products cast iron heads? I am about to install a set of new heads and the stock sending units and fan switch are too small for the holes provided in my new after market heads. I am interested on how other members may have solved this problem without causing the cooling fan switch, or temperature gauge sending unit to stick out too much and interfere with the exhaust or oil dip stick.
Thanks in advance for your suggestions.

 

Hardware store or Home Depot kind of place... plumbing dept, brass fittings, 3/8" - 1/2" NPT (pipe thread) bushing. AFAIK there's no fitment problem, only adds about ¼" to the height.