X0202 4 2006-05-11 0 0000006176 AMPCO PITTSBURGH CORP AP 0000807249 GAMCO INVESTORS, INC. ET AL ONE CORPORATE CENTER RYE NY 10580 0 0 1 0 0001185533 GABELLI MARIO J C/O GAMCO INVESTORS, INC ONE CORPORATE CENTER RYE NY 10580 0 0 1 0 0001238894 GGCP, INC. 140 GREENWICH AVENUE GREENWICH CT 06830 0 0 1 0 Common Stock 2006-05-11 4 S 0 1000 29.197 D 44700 I By: Investment Partnership Common Stock 45000 D The Reporting Persons have less than a 100% interest in this entity. The amount of securities reported as beneficially owned reflects the total amount of securities held by this entity which is greater than the Reporting Persons indirect pecuniary interests. The Reporting Persons hereby disclaim ownership of these securities in excess of their pecuniary interests. These securities are owned by GGCP, Inc. Mr. Mario J. Gabelli has less than a 100% interest in GGCP, Inc. and hereby disclaims beneficial ownership of these securities in excess of his pecuniary interest. GAMCO Investors, Inc. has no interest in GGCP, Inc. /s/ James E. McKee Attorney-in-Fact for MARIO J. GABELLI and GGCP, INC. and Secretary for GAMCO INVESTORS, INC. 2006-05-12