Weird issue with AFB

I picked up a Carter Competition 9635 SA the other day off CL . I went thru the carb and cleaned all the orifices , put it back to stock jetting ( assuming my web research was correct .. 95 primary/98 secondary and 7147 rods) and put it on my 360. Got it to idle fine but when I give it gas it dies then surges back to life over and over .
I checked the squirt shot and it look weak so I installed a new pump. Now squirt looks good .
started down the street and same thing…. When I hooked up my vacuum gauge to the carbs manifold port it read zero. So I switched to the ported one and got a reading of 5” at idle .
When I crack the throttle the reading on the manifold side jumps to normal but by then I am idling around 1600 rpm .
I did notice when setting up the carb that the primary throttle blades were a bit uneven so that when one side exposed the transfer port to square the other is closed ….
As for the surging I am using the same step up springs that I did with my 1406 so they shouldn’t be far off . Of course I cant get a good vacuum reading so its hard to know for sure .

Any thoughts ?