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Exhibit 23.1
CONSENT OF INDEPENDENT AUDITORS
We consent to the use of our report included herein and to the references
to our firm included in the Annual Report on Form 11-K for the NCI 401(k) Profit
Sharing Plan.
We also consent to the incorporation by reference in the Registration
Statements on Form S-8 (No. 333-14957 and No. 33-52078) pertaining to the NCI
401(k) Profit Sharing Plan of our report dated June 23, 2000 with respect to the
statements of net assets available for benefits of the NCI 401(k) Profit Sharing
Plan as of December 31, 1999 and 1998, and the related statement of changes in
net assets available for benefits for the year ended December 31, 1999, included
in this Annual Report on Form 11-K.
/s/ KOLKHORST & KOLKHORST
Kolkhorst & Kolkhorst
Houston, Texas
June 28, 2000
