I just double checked mine...okay like quadruple checked mine, and I am using the same booster pushrod (your pic "A") and I still had to use the spacer piece. My spacer piece is slightly longer than yours at 1 1/2" in length and I still had to adjust out the stock pushrod only slightly to get the appropriate drag on the m/c (or lack there of...something to do with pedal freeplay, I believe). I'm totally convinced that you should use the stock pushrod and the spacer doohickey.
Put a little anti-seize on the spacer, put it in the M/C, install the o.e. pushrod into the booster, mount the M/C & give the pedal a push... bet you get fluid outta that M/C then... Be sure to put the bleeder lines back into the reservoir so you don't make a mess.