This morning I made the decision to try and complete this job without help, unfortunately it went so well, I forgot all about photos until it was completed.
I took the reja / security bars and propped it in place with some supports, made sure it was level, then marked the locations for the support legs on the wall with a marker.
Using both my ordinary drill with a masonry bit, and my demolition drill with an SDS bit, I made the holes, which had to be 2 1/2\” deep.
That done, I put the grille in place, it fitted like a glove, it didn\’t even need supports to hold it in place, whilst I mixed up some cement and filled the holes, I then left it to start going off, and sponged it to blend in with the surrounding mortar. Job done… just got to paint it all now.