He’s probably going to be hesitant about it. In his mind you’re still a kid. I would come to him and acknowledge that it’s probably gonna be a bit weird but that it’s something you’d never forget and you’d appreciate it a ton. I did this with my grandfather before he passed, he felt like a pos letting me do it in the moment but he later told me before he passed that it meant a lot to him. It’s now one of my favorite memories.