Radio & steering wheel not working

[dsabc2867]

I just started working on my 92 ls400 recently. It sat in my garage for a year. The battery was dead and when I put a new one in it I put it in backwards. One of the fuses blew immediately and it was fixed. But now, I start the car and the radio doesn't work nor does the steering column controls. I have checked all the fuses inside and out. What could it be. I wanna get this baby running again. Thanks