Let's Build a 416 with Cast Iron Heads and Manifolds

can that extrude honing process still be done? that'd help open up and smooth the inside of the cast manifolds for better flow. i've not heard much about it since when was it the 90's? basically an abrasive paste forced through under pressure to 'port' whatever you're working on even where a die grinder won't reach.
neil.

extrude hone before.jpg

extrude hone.jpg

It has to help but I don't know if it's worth the price.