Aesthetikz

Hi everybody,
Our DD broke down, So we scrambled to find a used replacement.
We ended up with a 1994 Lexus GS300, And all was well on the test drive, And it drove 60 miles yesterday perfectly well.

Today it drove another 30 miles fine, Then on the return trip home I noticed the check engine light came on, And the Temp Gauge was pegged, So i pulled over immediately (On the freeway).
It started smoking pretty bad, Sounded like the engine was boiling...
It took a good hour to cool down just half way, In the low 50's, With rain. Called for a tow as to not risk it, And the battery was weak at this point as well.

The only thing we did different today from the past couple days is try and use the heater, And it kept blowing cold air.

It blew very hot air perfectly fine on the test drive...

I noticed this brown looking junk sprayed all over near the coolant overflow tank. There is a layer of the brown junk in the overflow, And I got a good look in the radiator where it was coated everywhere and very very thick.
I suspect it's something like stop leak...

I'm going to flush the system, But, Concerned that the (Stop leak?) has caused some serious blockage.
How should I go about dealing with this?

PS: It does not appear to be a blown head gasket, As it does not smoke, Has/Had great power and the brown crud looks more dark brown (Sort of sparkly) and chunky than milky and oily.

- JDB

Update:
Charged the batt and started her up. Noticed a faint white smoke out the exhaust, And found white smoke out of the radiator filler as well. Heard what sounded like air coming out of somewhere... Feared Head Gasket.
Noticed the fluid was no longer visible in the filler, Got a gallon of distilled water and started pouring until I heard a rush of water from underneath the engine, Found that the Rad Hose was completely off.
I wrestled it back on, Filled the rad again but it was still leaking pretty bad from the hose. Heater still blew cold, But, Temp gauge started to go down until the water was gone from the leaking hose.

Hopefully this is the problem? (Besides the brown crud).

I will flush and get a new hose installed tomorrow. But, Will a regular flush be enough?

*If this is in the wrong forum please move or notify me. Thanks.

Aesthetikz

Flushed the system, Changed Hoses as well as the Thermostat and Filler Cap.

Undeniably a blown head head gasket, Or worse...

If I put water in the radiator it wont start.
If I empty the radiator, It will eventually start.
White and sweet smelling smoke out the tail pipes.
Fuel in the radiator.

What are my chances of it just being a HG on this engine (2JZ-GE), Versus a Crack?
How long would it take a backyard mechanic to get this fixed?

So annoyed & angry.