Manufacturer Part Number: 110150R. 5.5 OPTIMUM R/M MAG BELLHOUSING CHEVY. Magnesium, Reverse Mount Starter, Chevy Bellhousing for 5.5" & 7.25" Clutches Reverse Mount Bellhousings. Quarter Master Reverse Mount Bellhousings are engineered with a durable, clam-style shape that strengthens stress bearing points and decreases spline wear.
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