That looks like it's got far hotter than you expect from just normal cylinder head temperatures. What do the bushes at the bulkhead end of the steady bar look like, and how are your engine earth straps ?
those looked fine. didnt reuse them but i have them as spares now :) they looked new to be honest. earth strap was fine too. whine bost does it connect to? the front most of the longer bold holding the bush?
if you had your earth strap connected to the longer bolt of the engine steady and the bolt was a poor electrical connection into the cylinder head (dirty threads etc) it will generate quite a lot of heat when the starter motor is running - certainly enough to cause the damage seen on the bush you've shown
I tend to run an earth strap from one of the starter motor bolts back to the body
Edited by KTS, 25 May 2019 - 08:02 PM.