Part number required

Hi,I'm hoping someone can help me. I need the part number for an original bootlid gas strut for a 1988 nova sr. I replaced the original failed one with an aftermarket one and destroyed the boot light switch when I didn't realise the new one was a different diameter. After a long search I found a replacement boot light switch but cannot put it in place as the aftermarket strut fouls it. I have found a place that does struts but there is a choice of three and you need the original part number. I have kept everything I have ever taken off my car except (sod's law) the old gas strut. Any help gratefully received

Here's the number mate 90119276

Thanks mate.