Hi,
Sorry to resurrect an old thread but..
Any tips on getting a stubborn cap off?
A bit late already anyway... it stripped in excruciating fashion

Had a proper 10mm allen but thought it was a little loose when i set off.. oh dear. Thought maybe next time to remember to crack it loose with the engine hot.
Finally had to coax by hammer, a socket adapter into the gap. I guess i could tidy that up for now with a Dremel or something.
Any tips for an online shop replacement? Ebay only seems to have some Chinese shops, and some rather expensive alternatives.