I ordered new overflow bottle from GKTech when they did their silly 9 dollar sale:
It is much thicker than OEM and stronger too, but the hose opening is too big to properly hold it in there and overflow hole is smaller because of the thicker material.
It took some time but I tracked down what was the reason why the engine overheated, pretty stupid that I had forgotten to cut a hole for the waterway in the head:
Correct gasket:
So I bought a correct gasket instead of making one myself that only comes off as rubble.
I thought I had a headgasket leak, so I had previously ordered a new from by Cosworth and ARP2000 headstuds with it:
Then I discovered the head can't be installed with studs in place, the chain guides get in the way. I removed the studs and installed the head:
I did some heat shielding too:
And assembled:
I have also been working on the new rear suspension:
