lower rt hand corner of the rad. as you're sitting in it. it's a petcock thou. not a plug so to speak. don't remove it. just turn it counter clockwise till it pours. rad cap off.
here's a FREE online only manual for your truck (it's a chilton/haynes clone),
http://www.autozone.com/autozone/homePage.jsp
just sign up, plug in your vehicle info, and go to,
REPAIR INFO / 1995 TOYOTA TRUCK 4 RUNNER (engine and 4x4 options go here)REPAIR GUIDE / ENGINE & ENGINE OVERHAUL / ENGINE MECHANICAL / RADIATOR
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here's a FREE dl of the factory shop manual for your truck,
http://www.ncttora.com/fsm/1990-1995....1990.1995.zip
parent pg,
http://www.ncttora.com/fsm/
cheers!
owner 93 toy 4x4