Temp Sender Questions 1990 Merc 60hp

[olyerickson]

Hi Folks!<br /><br />I plan to install an aftermarket water temperature sender on my 1990 Merc 60hp (temp isn't standard on this motor). I need to know:<br /><br />1. Where the "block plug" is that I'm supposed to remove to install the sender (not obvious from looking at the motor; seems like several choices)<br /><br />2. What thread size on the sender to get (1/8" NPT, 1/4" NPT, etc...)<br /><br />Looking at e.g. CP Performance:<br /> http://www.cpperformance.com/SearchResult.aspx?CategoryID=272 <br /><br />Thanks!