hey mate
I've decided to take a different route I think, tomorrow I am going to put the old lifters in that caused me to not have compression but still gave me oil pressure, I will see if I can build oil pressure with them in and that will mean it is the lifters that is causing the issue. if not that will mean I have put something together right.
I was very close to buying a 4k today lol and give up on the 5k but I will give it a shot tomorrow