Air Eliminator on Buffer Tank - best way install the expansion tank???

Folks - I'm still in design mode (as some of you know). I'm installing a boiler and it's oversized and I'm thinking of getting a buffer tank to make up for the oversized unit. The buffer tanks I'm looking at have air eliminator on top of the unit. The schematic of the piping on the boiler shows a typical expansion tank and air eliminator together in line. Since the buffer tank has an air eliminator, can I just place a tee in the piping and install the expansion tank directly (with a ball valve for replacing)?

Thanks and happy 4th

As I understand it, there should be nothing between the WH and an expansion tank. Now, I know they eventually fail, and having a valve to isolate it would be handy, but it is not allowed since it could be closed, and then you'd have problems with tripping the T&P valve. Other than that, the inspector will look at the manufacturer's installation instructions if he has a question about whether things are okay or not (at least he should).