Google has some very handy search features which render things like the forum search function obsolete but they're not very well publicised.
In this case, try copy and posting the following text into a Search Google:
site:https://www.the75andztclub.co.uk/forum "painted engine cover"
Actually, to save yourself the effort - click
Here. (If it doesn't work, you'll need to enable Javascript by clicking on the relevant button at the bottom of the browser window)
The
site: command is very handy and I use it all the time to find stuff on this forum, and the double quote marks force Google to search for exactly the words contained between them.