Hardin Marine has the correct billet alternator pulley for your Mando alternator. Just slide yours off and replace it with Hardin polished billet pulley.
SB Chevrolet 3 V-Groove Billet aluminum OEM style Crankshaft Pulley. This pulley fits Chevrolet V6 4.3L, 305 5.0L and 350 5.7L applications all years with a "V" belt. Replaces Mercruiser Part #90081A1 (OEM casting number 90081C)
BB Chevrolet 3 V-Groove Billet aluminum OEM style Crankshaft Pulley. This pulley fits Chevrolet 454 7.4L and 502 8.2L late model applications. Replaces Mercruiser Part #90081T1 and casting # 90081C. Pulley Specifications:
This beautiful show quality pulley is machined from 6061-T6 Aluminum and polished to a high lustre. This pulley is Direct replacement for Mercruiser pulley 15120T and fits all 4.3L-V6, 305/350 V8, as well as 454/502 BBC V8's. The diameter is 5.5" and the mounting bolt centers are 2-1/8"