Short answer, no. Mustang flywheel will not work with a 435 (witout changes) Best option is to get the 80's 302 truck flywheel. Odd options include an older car bellhousing. But that limits you in
clutch size. Mustangs were not nice to the 10.5" clutch, Bronco came stock with an 11" clutch back when the cars only got 10". About '86 Ford found the 5.0 was destroying the 10" clutch so ...