Let's see, where to start....
1. You didn't say how many miles are on the engine, so I'm going to guess something like 100-125K (?) (edit, sorry didn't read your sig before for the exact mileage, so 160k+ miles makes the following even more likely...)
2. All the way from NJ to CT with a stuck thermostat could have very easily stressed a head gasket. The fact that both rad hoses were cold (classic stuck thermostat), nothing was blown back into the overflow, and you were still able to add 24 oz of water (did this actually fill the rad?) means the coolant could have passed a head gasket.
3. Taking it easy after adding the water allowed you to almost get home. I'm going to guess that maybe your driving got a little more spirited once you knew home was within sight. This would have raised the load on the engine/coolant system causing a hot gas pocket to form in the system which, in turn, caused the temp gauge to spike (been there, done that
). Sorry, but flushing the system will not cure a blown head gasket.
4. Steering -- the SVX shop manual has an easy to follow set of steps to follow to see what is causing your problem. Have you checked the two fuses that are in the steering electrical system? Have you checked the output pressure of the PS pump? Have you checked the PS computer under the dash (it's bolted to the steering column)? My steering light came on on the dash when I lost power assist and it ended up being the PS computer that was bad (thanks to OT for a replacement!).
Hope this helps and best of luck getting back to enjoying your SVX.
-Bill
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'92 Fully caged, 5 speed, waiting for its fully built EG33
'92 "Test Mule", 4:44 Auto, JDM 4:44 Rear Diff with Mech LSD, Tuned headers, Full one-off suspension
'92(?) Laguna, 6 spd and other stuff (still at OT's place)
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