Dimitros-
My second welding project was a bumper for my Samurai. There were no drawings, just some careful thought.
The hardest part was buying and cutting and drilling two 1/4 inch thick 4x4x 4inch long angle iron pieces using the hold-down eye as a template. I used a felt tip pen to mark what needed to be cut off or drilled, vicegripped the two pieces together, and started grinding out the circular area - checking for proper fit - until I had enough material removed so that the bolt holes would have enough metal around them to hold. I also made sure that the face of the angle irons would be perpendicular to level ground so the bumper would not be "canted" top or bottom forward. Once the two angle irons were cut and drilled, I separated them and bolted them to the inside of the frame. This created two flat surface that I could weld my bumper to.
In my case I used a piece of 11 gage 2x4 inch box beam. You can use anything that you want although something flat works best with this angle iron mount. Add a winch plate, a receiver tube, brackets for a towbar, lighting holes, whatever. I turned my bumper into an air tank. Unfortunately, my welding skills at the time were not good enough to make a very air-tight tank so it never got used... HOWEVER - the bumper worked great! It didn't show any attachment weld failures for the 8 years that I ran with it.
I hope that this helps!