LINDBERG CORP <LIND> 1ST QTR NET Shr 15 cts vs 15 cts Net 689,561 vs 784,088 Sales 19.2 mln vs 19.8 mln Avg shrs 4.7 mln vs 5.3 mln NOTE: 1986 net includes a gain of 108,000 dlrs or two cts a share from proceeds from the sale of property.