the ecu is under the passanger seat if you move it all the way forward. you will be able to cut about 3 inchs off carpet. don't cut it off .. if done properly you will never notice it after your done . I can get a picture of it . but it won't be on a honda .the ecu is under the passenger side carpet
but for your 91 it's user the carpet under the daze board . just see if you can get to it .the ecu is under the passanger seat if you move it all the way forward. you will be able to cut about 3 inchs off carpet. don't cut it off .. if done properly you will never notice it after your done . I can get a picture of it . but it won't be on a honda .