Chevy vans... in this case, an older 3500 extended...
Seems there are a few of those multi-bend, short, heater hoses below the heater box...
Being a van body... there is NO WAY to get to this from under the rather short hood...
Figured out one must raise the front of the vehicle on short stands, take off the right tire, remove the splash curtain... and go in that way to replace the 'pretzel' shaped hoses.
So I take out the hoses and head down to the local auto parts shop... guess what... that part # was dis-continued... [grrrr]
Long story short... the guy at AutoZone let me go behind the counter and look at the rack of misc hoses... did not take long to figure out how to take a few of them and cut/splice them into what would fit and do the job.
While I understand the auto makers need to be efficient in design for assembly...
They are not (well not yet anyway) selling throw away vehicles (I understand in some countries that is the case).