Why are they not called “throttle body screws” or “throttle blade screws”? Plenum screws should be the screws that hold the intake plenum to the lower intake manifold.
some call it the Power valve.
guy on CL has an 08 altima motor w/80k miles for $150. i am suspicious of low miles and claim of good condition. pic does show other motors so maybe he is a good guy? as in, not just a random guy with 1 motor in his garage?
before you purchase and install a Nissan VQD35 V6 motor check the plenum screws and re lock tight them