I worked at a parts store as a counterman when I was 17, way back when. This was before PCs and modem linked credit card machines. We looked up parts in books and made CC imprints, kachunk lol!
It was pretty fun job back then and we all used to stick together for the most part. I will tell you this though, you really must enjoy dealing with the general public. It's a "service related" industry and the customer is always right, even though their wrong.
I met good looking woman with a '65 Mustang coupe and we dated for a while, that's the good part of the job is meeting all the new people.
The bad part is the customer coming back with a crapped out alternator ready to beat someone over the head with it. Then there's the customer who mis-diagnoses the problem and expects you to take back an installed part, worn and covered in grease and oil without a receipt or original box.
Oh yeah, the book (computer) wasn't always right. Give the customer a chance to explain.
Good luck man, I hope you like it!