It’s primed and sealed.
No more bog, only taken a month to get to this stage of making the plug!!
I am finally done with filler, i think it’s as symmetrical and straight as it’s going to get. Key take away, next time keep it simple with flat surfaces.
I think I went to complex making it with compound curves and trying to follow the cars profile too much
Anyway it’s done, final sanding to 1200 grit to go and then it’s ready to pull a mould from it.