Hi Gary I have favor to ask of you about the chair and how the seat rest between the spreaders. I plan on making a slight modification to the seat but I don't want to screw up the angle that it rests This is what I came up with so that I get a seven degree angle from the top of both spreaders I made measerments down 1 1/8" and the back 2 1/2" these represent the top of the tenons. The tenons are 3/4" thick 1 1/2" wide with spacing of 3/4" between them, so far these are just measurement nothing has been cut. Looking for some input. Thanks Jerry