either get a reman starter and mount gasket for it or take it to a starter rebuild shop and have it rebuilt.
Make sure you do replace the mounting gasket.
this is a generic parts lookup:
3001023 R - reman starter gas/lpg
178470 - gasket
If these are not correct then we will need a truck serial number to insure the correct part numbers.
If you want to make sure there are no screwups just take it and have it rebuilt at a starter shop.
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