Dumbutt Question.....

Solid lifter slants, have splash oiling on the lifter base, and just, for lack of a better word, drip oiling of the lifter bore.
Hydraulic lifter slants, have the lifters lubed, through hollow pushrods, rocker arms, and rocker shaft.
A FYI: the rocker arms, rocker shaft, push rods, and lifters are different between the two versions. As, of course, is the cam.