How does one go about adjusting valve lash with a compression gauge, i understand the concept but how are you able to crank the engine with the fuel assembly removed?

I don't believe turning it with a socket will get ya anywhere..

am i suppose to pop the fuel pump/ecm fuse? and re-install my alternator?

i did a head job on my car, i got spark, and fuel but only 70 PSI of pressure at #1 cylinder, didn't check the rest but im sure my valve lash adjustment is out of wack.

 

I wouldn't do it that way. Just as easy to crank it over to TDC, compression for that cylinder and set them both 1/2 turn down from zero lash. Then you're not guessing based on compression readings (or lack thereof).