I believe Reuters turned them into faster PDP8s via Microcode changes... 

-----Original Message-----
From: Ron Natalie <ron@ronnatalie.com>
To: 'Clem Cole' <clemc at ccc.com>, 'Dave Horsfall' <dave at horsfall.org>
Cc: 'The Eunuchs Hysterical Society' <tuhs at tuhs.org>
Sent: Sun, 21 May 2017 16:58
Subject: Re: [TUHS] Unix with TCP/IP for small PDP-11s

The 11/60’s main claim to fame if I recall was a writable control store.   Don’t know anybody who actually used that feature.