Place a rack in the center of the oven and preheat oven to 350 degrees. Lightly grease tube pan with solid vegetable shortening, then dust with flour. Shake out excess flour. Set the pan aside.
Place the cake mix, *1 cup (1 1/3 cup) undrained crushed pineapple, sugar, oil, and eggs in a large mixing bowl. Blend with an electric mixer on low speed for 1 minute. Stop the machine and scrape down the sides of the bowl with a rubber spatula. Increase the mixer speed to medium and beat for 2 minutes more, scraping down the sides as needed. The pineapple should be well blended into the batter. Pour the batter into the prepared pan, smoothing the top with the rubber spatula. Place in the oven.
Bake the cake until it springs back when lightly pressed with your finger and just starts to pull away from the sides of the pan, 48 to 50 minutes.
Remove the pan from the oven and place the pan on a wire rack to cool for 15 minutes. Run a long, sharp knife around the edge of the cake and invert it onto a rack, then invert onto another rack so that the cake is right side up. Allow it to cool completely. 30 minutes or more.
Meanwhile, prepare the glaze. First drain the remaining *1 cup (will be less if you used 1 1/3 for the batter) of crushed pineapple and reserve the juice. Combine the sifted confectioner's sugar, 2 T. of the reserved pineapple juice, and the lemon juice in a small bowl and stir with a wooden spoon until smooth.
Place the cake on a serving platter. Spoon the glaze onto the cooled cake. Spoon the remaining 1 cup (or less) drained pineapple on top of the glaze. Slice and serve
*Footnote* I like my cake moist so I use a little more than one cup of the crushed pineapple in the batter, 1 1/3 cup and the remaining pineapple in the other measuring cup. You don't need that much pineapple to place on top of the finished cake.