Cadillac: instrument panel, cadillac deville, side doors

Question
HI, I recently bought a 1985 Cadillac Deville Sedan and the motor runs great and it drives smooth, the problem is for some reasons the driver side doors, both front and back, will not open.  They are stuck in the locked position.  Also, the gas and climate control  gages do not work-they are both electronic, so I can't turn the heat or air on and the speedometer is not working.  What could all this be  and how would I be able to fix it? The gages that do work are oil and temp but these are after market because the motor had been replaced and the transmission is new.  

Answer
First I need to know ABSOLUTLY, The engine that is in the vehicle is it the IDENTICAL same style engine that came with the vehicle from the manufacturer.

Is the speedometer digital or analog ?.

Are the displays completly BLANK or is there a letter c or d on the display ?.