For glaze, in a small saucepan cook and stir preserves, lemon juice, mustard, and cardamom over low heat until preserves melt. Set aside.
In a covered grill arrange preheated coals around a drip pan; test for medium heat above pan.
Sprinkle ribs with salt or onion salt and pepper . Place ribs on rib rack, if desired. Place ribs, meaty side up, on grill rack over drip pan, but not over the coals. Lower grill hood.
Grill ribs for 60 minutes, brushing with glaze after the first 30 minutes. Uncover; grill for 15 to 30 minutes more or till ribs are tender, brushing occasionally with glaze. Serve with peach slices and any additional glaze.