The closest I did in a funeral mass was to do a lector / mass reader role. This was a couple of years ago. The First Reading as well as the Responsorial Psalm were texts already chosen for a funeral mass, so nothing out of the ordinary there. One difference was with The Prayer of the Faithful. This part had a line where the mass reader says the name of the deceased. Fortunately, I knew the deceased as he lived a block away from us, and so I was able to correctly state his name.
Request for a Funeral Mass Commentator
The lay minister who came to me asked me because all the other veteran funeral mass commentators had a family day activity that day. At least that's what the lay minister said. I didn't belong in that particular group and so "I was the only one he could approach."
Still hesitant on taking the role, I asked him if the funeral mass text (commentator's guide) is the same as the ordinary mass. He immediately said "yes". And I sort of doubted myself even asking that question. It turned out there are some slight differences. Nonetheless, I accepted his request to do the commentator's job.
Funeral Mass Commentator Guide
I was early at the morning funeral mass. The funeral service would occur right after the mass. There were a couple of mother butlers when I arrived at the chapel.
Just to be sure, I asked one mother butler if there was a certain missalette or guide or script that was used for the funeral mass. Fortunately, she was familiar with this sort of masses and immediately went inside chapel's repository. When she came out she was bringing this plastic clearbook.
"Alright!", I said to myself, for now there is a definite guide that I can use. This only reinforced my doubts on what the lay minister answered the day before. When I opened the guide, sure enough, there were a couple of readings in there. Then I realized I didn't ask the lay minister who would be the mass readers. Ugh. So I asked the mother butler.
She replied that it was common for any of the deceased immediate relatives to do the readings. I approached the children of the deceased, who at that time were in tears, sobbing. It was a bit awkward, but I had to ask who would read. Well, apparently, none of them were prepared to do any of the readings. I suppose nobody went to them beforehand and asked for mass readers.
At that moment, I just decided that I would take on the readings as well, and asked for the relatives' confirmation if it was fine with them.
Help from the Funeral Mass Priest
The officiating priest, luckily, was early. I approached him and asked if both First and Second Readings will be read. He had a preference and asked that only the Second Reading be read. I told him I was the only lector there and asked if it was alright if I could do commentator and mass reader roles. I added that the relatives were not comfortable reading. At that instant, another lector just came inside the chapel and the priest exclaimed, "There's your reader!"
Lessons Learned
There was only one copy of the commentator's guide. Naturally, when it was time for the lector's part, she took the guide. And when she recited the Responsorial Psalm verses, I didn't know when to give the response. The priest had a copy and just initiated with the response's first word.
So the lesson here is to copy the last few words of the Responsorial Psalm verses on a piece of paper so I would know when to recite the response. Again, this is because there is only one copy of the commentator's guide.
Another solution would be to create my own copy of the Funeral Mass guide for commentators.