i wanna know more bout slant sixes

Don't think International built engines for AMC. AMC & predecessors have a long history with the L-6. Here's a breakdown on the development of the last 6 cylinder engine family AMC developed.

199
The 199 cubic inch (3.3 L) 199 was produced from 1965 through 1970.

Applications:

Rambler Classic (1965-66, fleet cars only)
Rambler American/AMC Rambler (1965-69)
AMC Hornet (1970)
AMC Gremlin (1970)

[edit] 232
The 232 cubic inch (3.8 L) 232 was produced from 1964 through 1979.

Applications:

Rambler Classic (1964-1966)
Rambler American/AMC Rambler (1964-1969)
Rambler/AMC Marlin (1965-1967)
Rambler/AMC Ambassador (1965-1970)
Rambler/AMC Rebel (1967-70)
AMC Javelin (1968-74)
AMC Hornet (1970-77)
AMC Gremlin (1970-78)
AMC Matador (1971-74)
AMC Pacer (1975-79)
AMC Concord (1978-79)
AMC Spirit (1979)
Jeep CJ (1972-79)
Jeep Cherokee (1974-79)
Jeep Wagoneer (1965-1971)
Jeep J series trucks (1965-1970)
Jeep Commando (1972-1973)
International Harvester Scout (1969-1971)

[edit] 258

Engine bay of a 1980 AMC Spirit AMX with numerous emissions controlsThe 258 cubic inch (4.2 L) "258" in-line six was produced from 1971 until 1990. It featured an undersquare 3.75 inch (95.25 mm) bore and 3.895 inch (98.93 mm) stroke; it was otherwise similar to the 199 and 232. Later 258 models (starting with the 1980 model year for California AMCs, 1981 for California Jeeps and 1982 for all other applications) are equipped with AMC's CEC system.

Applications:

AMC Hornet/Concord/Spirit/Eagle (1971–1988)
AMC AMC Pacer
AMC AMC Matador (1971–1978)
AMC Gremlin and Spirit (1971–1983)
International Harvester Scout (1972-1974)
Jeep CJ (1972–1986)
Jeep Cherokee and Wagoneer (1972–1986)
Jeep J series trucks (1971-1988)
Jeep Wrangler (1987–1990)
Jeep Commando (1972-1973)

[edit] 4.0

Engine bay of a 1993 Jeep Grand Cherokee with 4.0 LThe 242 cubic inch "242 or 4.0 L or 4.0" straight-6 was an evolution of the 258 and 2.5 and appeared in 1987. It had the same 3.875 inch (98.4 mm) bore as the 2.5 with a longer 3.414 inch (86.7 mm) stroke giving it a displacement of 241.573 CID (3,959 cc).[1]

The 4.0 was discontinued at the end of the 2006 model year as the redesigned Jeep Wrangler uses Chrysler's 3.8 L OHV V6.