Owners/service Manual problems of the 1999 Jeep Wrangler

I have a 1999 Jeep Wrangler sahara v. 6. 5 speed manual transmission. My Jeep is in great shape however I started having steering problems. I noticed around the apex on on both sides the frame had rusted away. I had it a new piece welded in place and it was working great. Then I noticed my transmission was having issues. I thought I was going to have to buy another transmission when it was discovered the plate that lies below the transmission was rusted from the frame and not supporting the transmission. I had that welded too. I looked the other day and noticed a hole between the size of a baseball and golf ball. I took it again to my welder and he said the whole bottom of my frame is rusted away. I was told by my body shop that because of Jeeps design water was able to get and not out causing it to rust. The body of my Jeep is in great condition as well as my motor and transmission. Is there anything being done about this issue. If no once catches it I could have lost my front wheels and or transmission. I think its dangerous. I'm looking at $3000. 00 to replace my frame.