Coil, not spring.

If your hose is collapsing, that means the pump is evacuating coolant from the hose that is not being replaced from the radiator. Why not? Because the system has restriction(s) that is/are not allowing for adequate flow-----most likely the radiator, but it could be inherent design restrictions. Best to check for good flow.

If you are familiar with fluid pumps, a hose used on the suction side is very rigid, in order to prevent what we are talking about, but that's an open system---it doesn't loop under pressure like our systems do.

^^^ I learned something! I would add it, from a rod of stainless welding rod (maybe gratis at a welding shop) & continue the search if things are running too hot. #1 accurate gauge #2A too hot at idle/low speeds or 2B to hot out on the highway. & if so then what parts (shroud/stat etc) are you running? & rad might be partly plugged EDIT a partly clooged rad might not show up at low speeds but more likely will at high speeds so if it is OK at high speeds then it ain't the rad.

as easy as it is to fab and install, the spring [or whatever you want to call it] in the lower hose can't hurt anything, especially if you have a long section of straight hose, and if there may be some trouble getting all the air out of the system.
just my opinion, and i could be [more than likely !] wrong. wouldn't be the first time !

At $8.99 it's cheap insurance.

moparx and Montclaire I agree.

I appreciate the help from all and I know it's kind of a long thread so I don't think all read all my posts. The radiator is brand new. Now I suppose a brand new radiator could be clogged, but as I also wrote and pictured, I had the engine out, freeze plugs out, water pump out and flushed the block out, bypassed heater core. Yes, factory shroud in tact.

It never runs HOT on highway nor idling all but that one time, and I now have 800 miles on it since engine out. I don't think the temp gauge is dead on, but it's close. It just shot up that one day in very hot weather in very bad traffic. And it did immediately drop back down as we moved on.

RapidRobert; stainless welding rod. Um, good idea.

Pieces of rusty coil have been known to find their way to water pumps, sharp ends have pierced hoses...it IS possible for things to go wrong. Stainless steel is advised.

I once used an antenna-----that was a beech to coil up!!!

Larry did you do that blue paint job? Good job!

you are absolutely correct !! i should have been more specific, as i use a stainless wire every time i do this.
so, to those that are "rollin' 'em at home", use stainless wire to do so ! .075 wire or so. don't go TOO large, as it will NOT be "fun" to wind over whatever you use to fit into your hose. also, remember the wire will relax to a bigger size after it is wrapped around ??? to form the coil, so take that into consideration as well.
make sure you bend the coil ends to roughly a 90 degree inward, so as to prevent the ends from damaging the hose when you wind it in.