Cat c12 Boost leak. Looking for opion

I bought this truck few months ago and always suspected it had a good deal of turbo LAg. Not sure if its achieving full boost either. I think It struggles getting 20-25 psi and takes a while to get there. Up until today I just struck it off as the nature of this beast. So today I had time to look into if there was a leak somewhere and the first thing that came to mind was to look at the wastegate.
The motor is a 2003 c12 non bridge motor with serial number prefix 2ks
I removed the little hose to the waste gate actuator and put 30 pounds of air to the nipple and guess what, there was a major leak, the air just blows straight through the back of the actuator with no restrictionat all. so I guess obviously the diaghpram is destroyed. I have been wanting to disconnect the hose anyway and just fold it to pinch it off and zip tie it. I did as much reading as I could and found that guys have been doing this for years on older motors. I want to do this but would like your input. Do you recommend replacing actuator?
Next, obviously I have to remove the bad actuator to make sure that wastegate is closed and nut stuck partially open. Need your thoughts on a good method to free it up and make sure it is closed fully if I'm gonna just delete the actuator.
LAst, with all that air free flowing freely through the actuator, would that be enough to cause all that turbo lag and not full boost? I assume this is causing bad fuel milaeage as well.

I appreciate your thoughts and advice

 

thanks for the response my friend. YEah I figured boost wasn't too far on the top end. Its the lag and that huge airleak has to do something with it. I cant afford the expense of a new turbo just yet but I'm sure this truck could use one as it is the original turbo. truck has 570k on it with original turbo, however, it had a full rebuild with updates done by caterpillar dealership 250k miles ago. When it comes time to replace the turbo, ive been thinking of doing one of those non waste gated bully dogs or pdi turbos. So for now, I would just like to get rid of the lag

 

sorry for the confusion, I cant move the waste gate at all with the actuator attached to it. All I know is all of the air comes right out of the actuator housing in full force. major air leak. I'm going to try and remove the actuator tomorrow to see if the wastegate moves at all. if its frozen, I'm gonna have to try and free it up and get that sucker closed

 

I remember on one pull with 23 tons 2 days ago, I couldn't get 20 pounds. then on another pull I did get 20 pounds. That's why I suspect a boost leak. not to mention the ridiculous turbo lag

 

ok thank you. like I said, just want to be able to hold out for a little while. would like to upgrade the turbo eventually