That is exactly what I used, a butter knife with a cloth under it. I pinched mine off the wife, it is the old type about 1/2 inch wide blade rounded at the end and very thin. I bent it slightly about 1/4 inch from end of blade, so that once under the lip, the bend rolls on the cloth and out it pop's. Do not go near it with a screwdriver even a terminal one as the blade is too thick and you may end up damaging the old light but more importantly the surround.
The puddle lights are very easy to get out, they have a little recess and you can quickly lever them out and it takes seconds.
Now if you fancy being a little more funky, why not change the standard bulb's in all if the remainder of the internal lights with coloured LED's, mine are now all blue except for the map lights. All are as easy as the puddle lights to remove except for the glove box as the recess was at the rear, so had to use a little hook tool I have to get it out. I even did the boot lights. The only one which was a pain was the ceiling one but once you get the cover off, 2 sec's to replace the bulb
No great skill to take the lights apart, just a couple minutes of your time for each one, took me about an hour in total start to finish.
I got 10 LED bulbs for £5.68 off Amazon a couple of years ago.