[speedfreek]

I have a 1989 gt. I would like to upgrade the engine to a 351. Any suggestions? What year block is the best? Would like to keep the T5 and EFI. I have a 1973 cleveland, but was told it wont work?

[EagleAutosports]

You could use the Cleveland if you want but Cleveland parts are more expensive.
Either 351 you get will need a swap kit that includes the 351 distributor, oil pan and pump, 351 oil pump driveshaft, 351 intake, 351 swap headers, and accessory brackets. Then you'll need a cowl hood for clearance to the intake.