2 bc_author, /* user who last set the bit count */
3 pers_rp bit (18), /* name of user who set the bit count */
3 proj_rp bit (18), /* project of user who set the bit count */
3 tag char (1), /* tag of user who set the bit count */
3 pad5 bit (2),
I believe "pad5" should be "bit (27)".
Actually, maybe not. Looking at the actual data shows that packing is different then I calculated.
Closing as ticket moved here: http://multics-trac.swenson.org/ticket/24