Yes Richard it is a stressful time replacing those filters,

I remember very well pulling apart the Canon 5D, it gave me a headache, and took a number of hours but all was well after the event.

If that little red light doesn't fire up at the switch you know it all went wrong,

I have done another two successfully after this.
Glad to hear it was only a cheap camera to start with, at least you know what to expect the next time, if there will be a next time.
Leon