In message , Jim
Bowen writes
I have a Rayburn 200SF solid fuel cooker. The bottom firebrick are
deeply pitted, and I think they should be replaced. I can buy the
firebrick online, but I can find no instructions/information on DIY
replacement.

There are various installation manuals on the web, which seem to show
initial installation, which should help. Just Google Rayburn
installation manual.

--
Graeme