Picked up a 2024 Ai-One Jailbird Cruiser from the trade-in bucket at Edwin Watts yesterday for a song. The head is nearly perfect, but the grip has some grime that I'm having trouble getting out. Tried Dawn, alcohol, Goo Gone, Windex, grip solvent, and even a drafting eraser without much success. Any other suggestions? I like the grip and at least it's sterile now, so I won't replace it right away.