Yep, they fitted without any issues. I tried to fit a YSS shock to my NC30, the remote damper fouled the tyre!
You know the likes of Hagon, IKON etc were making these shocks for the 400/4 and other SOHC's when they were still curren. However, the likes of the Chinese and Taiwanese brands say their shocks fit a huge number of bikes when in fact they don't and especially the old clunkers we ride.
Hagon might be expensive but at least you know they are tried and tested and British made. TEC used to make decent shocks for the 400/4 that looked OEM (but were 5mm shorter in length). They ran out of stock last year but I was told they were going to get some more manufactured. Give them a call, they are based in the north east of England. They tend to concentrate on the new RE's, BSA and modern Triumph's these days.