US '96 FZJ80 here,
As far as I could tell there is only one 16264-66021 hose. It attaches to the rear tip of the #2 water bypass pipe, running under the throttle body, and seems too long to attach to the rear heater-core feed pipe against the firewall.
The #2 bypass pipe is the skinny tube that...
Gates tranny oil cooler hose, SAE 100R6, 3/8" id. Available at Advanced Auto Parts, among others prolly.
Rated to 400psi and 275Farenheit.
The 15mm constant tension clamps from Bel-Metric fit these perfect with a little silicone to slide them over the nipple bulge.
For the stubborn 3/8" Gates line: Dunk the end in really hot water for a bit (close to boiling), spray it with silicone, force it over a 3/8" ratchet extension held in a bench vise, and let it semi-cool like that. This will stretch it out very nicely to fit snugly over the paper clip cooler...
Yes! This👆
That’s exactly what fixed mine as well (though my soldering looks nowhere near as clean as yours!)
The white wire holding ground had rubbed itself shy after 300K or so, this was a cheap, simple and lasting fix.
Try wiggling the wire with a weight on the brake pedal to see if this...