As per a previous post that when I fitted the rocker cover I noticed that it was not sitting flat and there was a definite bow causing a gap in the centre section of the cover. I placed the cover on a flat surface and with a hammer and a piece of hard wood onto the flange straightened it …… but I was still seeing some oil seepage.
I have previously read where owners had used two rocker cover gaskets instead of the one. So I have tried this and so far all seems good.
MGB tips mods and maintenance 