Nos. 91-1428, 91-1483. Argued October 26, 1992. Decided December 15, 1992. Laurence D. Steinsapir, with whom Henry M. Willis and Susan L. Catler were on the brief, for petitioner in No. 91-1428. James T. Winkler for respondent in No. 91-1483. Margaret E. Luke, Attorney, N.L.R.B., with whom Jerry M. Hunter, Gen. Counsel, Aileen A. Armstrong, Deputy Associate Gen. Counsel, and Linda Dreeben, Supervising Atty., were on the brief, for respondent in No. 91-1428 and petitioner in No. 91-1483. Petition