I had this problem with a SuDoKhoi I scratch built.... I just cleaned out the engine bearers down to solid material and squared it off. Then I cut a piece of hardwood to fit. Then mount the piece and drill 1/8 - 3/16 holes thru. You may have to drill at an angle. Now epoxy the blocks on with 1/8 - 3/16 dowels thru the holes and you'll be set as soon as everything drys.... Worked like a champ!!! A year later, I had an engine flame out in a hover on this bird and she went in pretty hard... broke a lot of other things... but not the engine bearers!!!