ID THIS BLOCK

Good Morning
Killer6 thanks for the info on the torque convertor. Hadn't gave that a thought. I do plan on keeping the valve train solid lifter. No cam/lifters came with the motor, only pushrods that I haven't examined yet.
Forgive my ignorance, on the deck where the displacement is stamped it followed by the letter 'R'. If it was a hydraulic lifter motor wouldn't it be stamped 'E'? There is an 'E' stamped further down but it is by itself.
Thanks Again for the input.
'64 Dart