1995 Pontiac Firebird oem spark plug wire specs

Electrical problem
1995 Pontiac Firebird V8 Two Wheel Drive Automatic

I recently had a shop replace my spark plug wires. They were the original factory wires.I told the shop I wanted the old wires back. Well I picked up the car and just assumed they put the wires in the trunk area. They didnot I found out about a week later. Today I called an auto parts store that I know sometimes sells to them and they said the factory wires were 8mm so later today I got under the car and while they appear to be new wires they are only 7mm wires.I would like to know what the car came with from the factory as I was told they would be replaced to factory specs. Also they charged me $169.00 for the set so I was expecting a pretty good wire and not the bare minimum or below factory specs.C one of the car pros guys give me an answer as to exactly what the factory specs are as to what the car came with originally. Thank you and I hope to hear from someone soon as tomorrow after work I am going to replace the distributor or I should say get as much done as I can and finish up on Thursday. If the wires I have now are too weak I would sure like to know while I have the front end taken off and the wires are easy to get to.