[TUHS] 4.3BSD-Tahoe Restoration

Hello All, I am attempting to restore 4.3BSD-Tahoe to a usable state on the VAX. It appears, based on the work that I have done already, that this is possible. Starting with stock 4.3BSD I got a source tree into /usr/tahoe and using it I replaced all of /usr/include and /sys, recompiled and replaced /bin, /lib, and /etc, recompiled a GENERIC kernel, and from there I was able to successfully reboot using the new kernel. As far as I can tell (fingers crossed!) the hardest part is over and I'm in the process of working on /usr. My question is: how was this sort of thing done in the real world? If I was a site running stock 4.3BSD, would I have received (or been able to request) updated tapes at regular intervals? The replacement process that I have been using is fairly labor intensive and on a real VAX would have been very time intensive too. Fortunately two to three years' worth of changes were not so drastic that I ever found myself in a position where the existing tools were not able to compile pieces of Tahoe that I needed to proceed, but I could easily imagine finding myself in such a place. (This was, by the way, what I ran into when attempting to upgrade from 2.9BSD to 2.10BSD, despite a fully documented contemporary upgrade procedure). -Henry