Mark it up and drill first hole.

Now cut it out with a jig saw.  I used heavy duty duc tape to hold the cut part as I went round.  This stopped it flapping.

Glue and clamp the internal framework.  I used a piece of MDF which I marked out and jigsawed a matching hole.  I tested the fit with the window before fitting.  This method was suggested to me by the joiners here.

Now install the window.

And this is what it looks like from the inside.

Onto window 2.   Unfortunately there are struts everywhere as seen here.

Cut em out…..  I used an angle grinder (carefully).

for the framing on this one I just cut 4 bits of wood which allowed me to adjust them after the hole had been cut.

And from the outside.

Cut little corner blocks and install the rubber.

Install the window.

That’s it for this time.  I will do more photo’s over the next few days.