Small block pushrods with hydraulic cam.

Are you sure? The T/A heads had different adjustable rocker arms than the 273. Will the pushrod length work with the different geometry?

340 T/A AAR used a hydraulic cam.
273 used a solid cam.
So, no. Totally different pushrods.

Im building a 340 hydraulic cam, adjustable rocker motor as we speak. Through my research, 340 t/a pushrods are what you need to use. Despite having offset rockers on the 340 t/a heads, all the pushrods are the same length. The Summit pushrods I mentioned are suppose to be the hot ticket for this combination. I will report back when I get the valvetrain installed.