No, a wishbone overdrive transmission (like the Ford Toploader with an overdrive unit added) is not a direct bolt-on for a Ford 351M engine. The 351M uses a different bellhousing bolt pattern than the transmissions typically associated with these overdrive setups. You'd need an adapter plate and likely significant modifications to make it work. It's a complex and non-trivial undertaking.
A much more practical approach for an overdrive on a 351M would be to utilize a later model Ford transmission designed for that engine family, such as an AOD (automatic) or a T-5 (manual) with an appropriate bellhousing. These are far more readily adaptable and require less custom fabrication.
