Thanks Grigg, I agree, that I will have to find it out for myaself. However, if the factory had put in an open driveline, all the axles would have been built with the same geometry, based on the angle the engine / trans were mounted. I can find the trans angle relative to the frame, once I get my engine here from Nebraska. If the rear axle were to move verticly, without changing angle as the springs compress, then it wouldn't matter if the springs are sagging or not. However, my placement of the axle along the arc of the spring will matter. I think that I am going to use the kit that moves the axle 1.5 inches back. It looks like it will better center the wheel in the opening. Because the spring is an arc, I will need to place it and measure for myself for the best result. Otherwise, I would be confident that anyone mounting a rear axle on stock springs in the same way with a stock motor mount would have the same angles. AS you say, I can always add shims if I have to.
