[V8Vairs] What's being used for cooling system pipes?

[Thomas Robert R Civ 76 PMXG/MAEAPF]

Dewey! I need to come visit you. I can't even get to Cliff's house 2 miles
away, though. I'll have to make an appointment to visit with after work some
afternoon. The club Christmas party and monthly meeting is tonight. maybe
I'll see you there.

After pondering what people have said and doing some research,  I'm thinking
of using flexible PVC tubing because it's fairly light, the flexibility
lessens the cracking, and it's pretty cheap. But up until the day I buy the
stuff, I'm open to suggestions.

Bob Thomas