short travel lifter .058
 

First question, what is the benefit

Second question, how much preload

This going into an LS7 engine

This is not an Advanced Engineering Tech question. Take it to one of the engine forums.
The benefit of a short travel lifter is less potential for pump-up.
I have no idea of the preload. Call the mfr. or vendor.

.038 cold preload. Will be .028 when it heats up