Ok i have been hearing about making an injector pop off tester .

What is needed. I do have an old fuel line with the injector side nut on it. Other side is cut off.

what else do i need and how to do it.

Would it be wise to rebuild injectors or buy new injectors? I ve heard of checking pop off pressure on new injectors as well.

Also what about installing these newly calibrated injectors but staying with the same pump(dont know if or when its been replaced(anyway to tell))
will an old pump be able to pop off the higher pressures (Im assuming an old injector pops off earlier along with leaks,etc.)

 

I was able to buy new tip assemblies to rebuild mine, was more about avoiding the hassle and expense of shipping cores across the border than anything. New injectors are so cheap it is not worth having old ones rebuilt unless you have time to just tinker around, and can find someone willing to sell the parts (seams mostly a closed shop thing on selling injector parts) FWIW.
The tester is easy- get an inexpensive hand pump, a 0-3000 guage, I welded an old line into a fitting.