260 V8 choke heat tubes

[A V8 Al]

The two choke heat tubes on my 260 V8 Falcon Sptrint have rotted and broken off at the point they enter the exhaust manifold. What is the best way to remove the remaining tube from the manifold. Also, how are the new tubes secured to the manifold holes?...is it fust a pressure fit? Thanks, Al

 

[Blue Futura]

I drilled mine out on a 289 , very careful so i would no oversize it. Then just installed another new one . It fit's a little loose but stays in and works good .