I'm not one to rat some one out to the feds, but I'm really concerned that some unsuspecting pilot is going to get hurt with an aircraft that is being worked on by 2 non A&Ps. This aircraft sat in the weeds on OKH's north side for well over 15 years because I told the owner his aircraft had serious corrosion in the rear wing spar and refused to do an annual. Now these two pilots have dragged this beech musketeer out of the weeds, removed the 160 horse engine and installed a 150 used Lycoming. (no paper work) They are now cleaning the aircraft and getting it ready to sell. FSDO is not working So I'm really at a loss as to what to do.