I decided to make the engine mount to the same dimensions as shown in the supplementary plans. The main part of the engine mount is the tray. Be accurate with this and everything else should fit together. I made up a jig of steel angle clamped to a table. The steel was cut and fitted in the jig so that I could weld the spools to the main steel tubing. I then turned the pieces over in the jig and welded the cross pieces.