Thanks to all your inputs, I took a chance and started the job. I almost gave up when I couldn't get the nut at the frame out, it was so tight. I got the electric impact wrench from Harbor freight for 49.99 with 240lb-f of torque and try to open it, it didn't even move. With lots of WD40 and many times of trying, finally the nut came out.
I got an air compressor for Xmas, and got the Harbor Freight set of air
ratchet and impact wrench.. Woo.. now I'm a real Garage Man!! (insert
Tim Allen noises here)