318 Heads: bad valve job?

66fs said

Brake fluid is expensive and corrosive. I usually use kerosene or diesel fuel and maybe a little automatic transmission fluid for color. I mean't so you could check the seal on the valves with the seats without taking the heads apart. It is a rough check but works pretty good.

Click to expand...

As my heads are out of the engine and unpainted, is that a problem?
Brake fluid will corrode the metal and or maybe seals as well?
D*mn!

I got brake fluid very cheap here, thats why I used it.
Lets see what I find first, but I think I'll run 69 Cuda 440's tip, alcohol and red dye, as thats easier to run into.

Considering my heads will be set apart for a while, should I coat them with something?
WD40 maybe?
It is pretty humid down here...

Thanks!