How hard is it to add rear defrost ?

 

Very easy, replace the rear glass with a defroster one and wire it in.
I'm being a bit flip because I think you meant how to add defroster elements to the glass. Pretty much impossible for the home mechanic, certainly more trouble than its worth.
if you swap the glass, I think I remember from the non-defroster model i stripped that most of the wiring harness is there, you will have to run the heavier guage wire to the rear from the fuse panel and install a switch. Iirc the harness is there behind the dash.
You should know that most cars came with defrost and that many people are looking for non defrost glass for show cars or cars with tinted rear glass. You can prob get some decent money for the non defrost glass.

 

I have a rear hatch w/ defrost available if you're interested. I could probably dig up some wiring too. I'm 35 miles NW of Savannah...I don't think that's too far from you. PM me if interested.

-Tom

 

besides the switch, wiring to the rear glass, and the rear hatch w/defrost.... what else is needed?
I have a 1989 firebird. is there also a timer or relay to add?

 

Find details here:

https://www.thirdgen.org/forums/elec...defroster.html


Good luck !

 

The timer is built into the switch. I added all the wiring to install rear defrost on my car minus a replacement hatch glass with the heating element on it. Been dragging my feet on it since that hatch is a heavy sucker to remove without help from a friend.

 

Thank you sir!