Begin by removing the covers to your 1993 Geo rear speakers. Remove the speaker retaining screws. Remove the wiring harness from the back of the rear speakers. Reverse the process to install the new rear speakers.
Just scroll through the questions on this site. It's been answered already.
The door speakers in Geo Prizms From 1993-1997 and possibly newer are 4in. and the rear speakers are 6.5in.
Rear deck speakers are 6" or 6 1/2" and the door speakers are 4"
See the answer for the 93 model if you're referring to the rear ones. If you want to replace the front ones, you have to remove the door panels.
How do you replace the timing belt on a 1994 Geo Prizm 1.6?
See the related question: How do I replace the water pump on a 1993 Geo Prizm 1.8L?
4" in the dash, and 5" in the rear deck if it's a sedan, or 5"x7" if it's a hatchback. Hope this helps.
From under the car.
1995 geo trunk lid bulb
Front or Rear? Both
You may find some help by searching for this question.How do i replace the water pump on a 1993 Geo Prizm 1.8L?
Remove the old mount & replace with the new.