If I don't use a res how do you bleed the system?

Also I know guys have used a cobra res with success but I doubt I'll find one in the junkyard.

One more question, does the res tank need to be the highest point of the system, I'm 99.9% sure it does just want to confirm.
I don't think a 98 w-body coolant res would be higher than the ic core, but I could be wrong...

Thanks for your help!