Bypass water fitting question

OK boat guys - answer me this one:

I am about to re-install my intake manifold (remember all I wanted to do was change my oil) and I figure it is a good time to replace the corroded water fitting that screws into the intake manifold on my '68 289 Interceptor (Ford). I am having difficulty locating a 90 Deg hose-to-pipe fitting that has this extension that protrudes into the manifold. What is the purpose of the extension and do I need it? Can I use a regular fitting that does not have the extension? Who sells these strange fittings?

Thanks in advance - I am confident someone here will have the answer.

In the mean time I am going to install the corroded fitting. (The fitting in the picture has already been buffed on a wire wheel.)

So how's the oil change workin' out for ya?

Hard to believe how some of these projects go south huh? Another reason why I never lift my motor box cover without adult supervision.

BTW.. nice to see you on..you ain't here enough.

john