I couldn't put it off any longer... The garage was getting in a total mess and was in serious need of a tidy. Frustrating but I've always felt better after getting things in order and it allows you to think about the coming jobs. A couple of hours spent tidying still left me some time to start preparing the outer door frame.
Although before the clear up I did have to pop to the builders merchants to pick up a couple of bags of builders sand. I have to brick up the gap underneath the outer door frame so need the sand to mix some mortar.
Although I had secured the door frame reasonably well to the brickwork it still needed some further frame screws attached. I've used pretty much the same screws as uPVC window/door fitters use. They are designed to drive directly into brick/masonry and effectively cut their own thread into a 6mm diameter pilot hole. I may well have mentioned them way back when I first attached the outer door frame - they are 150mm long and I bought some suitably long masonry drills as I simply drill through with the frame in situ. I may need some more but I used the last four I had for the time being securing near the upper and lower hinge positions.
I also removed an old timber from the original wooden lintel and cleaned away the dust and loose mortar from around the opening.
That's about it I'l next need make some timber packing around the door frame to fill the gaps on the outer edge and then I'll be ready to make and fit the outer door.