Drop the panel under the right foot well and pull the glove compartment. Maybe you can do it by simply removing the glove compartment. Don't replace the amp without making sure you have fused the auxilliary pump because a stuck auxilliary pump with no fuse will take out the amp.

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1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13