Identify what version of Lisa 2 you have: A Lisa 2/5 with 3 DB25 ports on the back or a Lisa2/10 with only 2 DB25 ports on the back.
Check the the label on the PS and verify that it's the correct 110 or 220 version correct for your area.
If you have a Lisa 2/10 then just try to power her up, you can do no wrong.
If you have a Lisa 2/5 then first open the back cover and verify the batteries have been removed from the I/0 board. If they are there remove them immediately and most likely you will have a major corrosion issue to fix. If the batteries are not there then look for corrosion on the board in the lower right corner. If it's clean ( doubtful ), then try to power her up.
Your floppy drive will most likely need to be serviced (cleaned and lubed), and your keyboard will need to be rebuilt with new pads.
If you have 2/10, the HD may sound like a 747 taking off (this is normal), but don't be surprised if it does not work, if it does, catastrophic failure is imminent.
Good luck.
Rick