The LX has interchangeable finder screens. The stock screen has a split image with a microprism collar. Easy focusing with that combo. Metering - if set to "Auto" it is aperture priority. The aperture can be seen in the little window at the bottom of the VF, the meter indicates the applicable shutter speed by lighting up a diode by the speed. If you are in manual mode the shutter speed you've chosen is shown with a pointer to the speed scale, what the meter suggests by a diode as above. You thus have the choice of changing the shutter speed manually to agree with the camera's suggestion, changing the aperture, or ignoring the meter. BTW, about the only flaw with the LX is the lack of an AE lock, so while in AE you
can't use the center weighted meter to, for example, meter a backlit face close up, lock the reading and then step back for an exposure with the face off center.
You'd have to go to manual, set the exposure as described above, then recompose, or whatever. The LX has one of the most sensitive metering systems ever, from - 6 ev to I think 20. You can truly shoot by moon or starlight, and with the exposure reading taken off the film during exposure changes in light during a long exposure are compensated for.
Michael Butkus has the LX manual on line here:
Pentax LX user manual, instruction manual