It's not fun at all. Ive changed them on 2 different motors. I was rebuilding them in the first place because I bought the trucks with bad engines. 1 motor had been apart before I owned it and all 6 tips broke off when I removed them. The other one was a complete nightmare. Broke off the heads on all 6 ended up drilling out the glow plugs. I'm sure mine were worse case scenarios, but there is no easy way. Might get lucky with lots of wax and a ton of patience