Better off using a screw type lamp bulb the size of a golf ball and a coke
botle lid with a pen if thats all thats available or the stem from the unforunet yet also commom broken pip. You always have to option of A) heating and using a needle to poke a hole or B) Puting a second hole in the botle lid and loading the bulb by screwing the lid on and off. If your gonna go down this path and heat glass and start poking holes Id sugest investing in a few test tubes but as this thread started off in times of need heat and poke ur holes with a needle lol
How is the pen secured to the bulb? Car light bulbs are very very tempermental and unless you use a drill to drill through the guts of it 9 times out of 10 the whole meal casing will break off leaving only the circular part of the globe and I wouldnt waste my time poking holes in it.