correct air cleaner?

Hello, can somebody tell me which air cleaner assembly is correct for a 351 2V engine? I've seen two different snorkels on many 70 era ford car blue air cleaners - 1 has a shorter snorkel. The longer snorkel also has the round part on the top. What is the difference?

Thanks for any help.

Hello!

The short snorkel is for a 351 windsor and other is for the cleveland.

Ray

thanks again, Ray!!