I think you might have to get your son to do it, as it does require a far bit of contortion work to get under the dash. There is the pin, and when you put it all back, you need to take it in and out a few times to get the adjustment to the connecting shaft the right length. Then getting the nuts on the studs is a bit fiddly. I took the bottom of the dash out in the end to make it a bit easier.
It's worth changing the Slave cylinder while at it, as in the past, both times I have had to do the master, on other cars, the Slave went while I was bleeding the system. On my T2, it was the other way round, the hose to the slave went, then while trying to bleed it, I thought the slave went, then once that was changed, and I was bleeding it, I discovered it was the master that had failed. I should have learnt from the past.