Long trip planned

Hey guys, Newbie here.
My g/f and I are taking her 95 Lumina w/84k on the odometer on a long road trip in about a month. I was wondering if there was anything I should particullarly look out for when I do my pre-trip inspection (I'm not familiar with the service records of the car, or the car itself). Any help would be greatly apprcieated!

On a side note, she wants me to install remote keyless entry, is there one specifically made for the car and/or is there one that works well with the car?

95 Luminas had keyless entry as an option. I'm not sure how hard it would be to implement a the system on a car that didn't have it.

As far as the trip..how long are we talking about here? You should maybe change the oil. Check the serpentine belt for wear. Change the plugs. Check the brake pads...see if they have a lot left on them. Have the alternator tested to make sure it's still charging good. They were/are notorious for going out on GM's 60* and 90* motors.

That's about all I can think of. Last time I went on a long trip, I didn't check anything. I just went. :)