Mk5 fuel pump questions

[Nonsense]

Hi guys. My fuel pump is leaking really bad. It's a 1995 mk5 2.5Di non banana with mechanical bosch pump. It's been to a diesel specialist half a year ago which supposedly replaced all the gaskets but its leaking again. I want to do it right this time meaning I want to take off the pump and service it myself. Is it a DIY job or do I need to have some special tools or knowledge? Can someone explain how to take it off and then refit it? I already know how to lock the engine with the pins etc I assume this is going to be the first step.

[Chug]

https://www.youtube.com/watch?v=_01gEg2ZMwg video from bosch shows how to take apart the pump
and also
https://www.youtube.com/watch?v=pPIT0CdswPI&t=468s

It is pretty simple really the only tricky part is the small spacer that can fall out when trying to replace the distribution head and springs, if you are going to do it, make sure before you do anything that you accurately mark the position of the front flange to the shaft as you will have trouble getting the timing right if you don't get it back right, it's not got a keyway to align just a tapered shaft.