@david hill is currently breaking in the rebuilt engine. He recommends that the radiator hoses, which he and I had replaced about 2.5 years ago, should be replaced (more on this below). I checked on Rock Auto, and they have the following Continental and Gates models. I don't know, but to the eyes of both David and me, the pictures look rather different!
The Gates 20630, which works great on my 1970-1971 Dodges, is not correct: I had bought one back in 2021, and it did not fit Buttercup -- so David had to replace it at the time with a local NAPA part. The Gates 20630 hose is still in Buttercup's trunk, for possible use on a Dodge:
That NAPA upper heater hose from 2021 is now getting changed. David thinks that the likely cause is coolant contamination. Off the car it will thus go after break-in, as will the lower heater hose (which David tells me is swollen at both clamps).
The hoses that David asked me to order for Buttercup this time are Continental (upper) and
Gates 20663 (lower). The question was, which is the right Conti part number?
--> For my 70 300 TNT 'vert, I used the Continental 60664 as that was the unit that the manufacturer recommends for a 440 with A/C (and it matched exactly what David had on his own 1969 300 TNT 'vert, see
here; BTW, for that Chrysler also, the Gates 20630 was listed as compatible on RA but did not work).
--> However, for a 1972 T-code Chrysler, the Continental website says P/N 60621 for a 1972 NYB with A/C and P/N 60664 for one without A/C.
I am puzzled, because David and I think that the 60664 should work too (
@lemondana said, in another situation, that
both the 21 and the 64 should work).
Sooo, being curious, what I have just done is to order both (plus
a Gates 20663; Edit: by mistake, I ordered the Continental 60659 -- it should fit, we shall see), and then we can see if it matters for the upper hose whether a 1972 Chrysler with 440 has A/C or not.