BigNasty
If the valve covers have 6 bolts you have a Windsor....the Boss used Cleveland heads on a Windsor block. How do you know they are 351 Windsor heads?????
Look at the intake ...if it has the firing order stamped on it and it is 15426378 it is a 289/302 block. If it is 13726548 it is a either a 351 or a 302 HO. The 302 and the 351w look very similar at first glance. The 351w has a slightly higher deck height than the 302.

302/351 windsor valve covers

Boss 302 valve covers/351 Cleveland
Keith/Bumble
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