My GTM Spyder is described on it's V5c as a CTM Spyder. I'm guessing that the original owner/builder's handwriting on the form wrote a G that looked a bit like a C so that's what DVLA put on the registration. I'm also guessing that they were so relieved to get a registration they didn't bother getting it changed, or maybe they did try and it wasn't easy/possible.

Its not a big deal but I'm wondering how easy it would be to get this corrected. Before trying I just thought I'd see if any of you clever folk have been through this before. If its a real pain then I'll just stick with the C. If its just a phone call then I'll do it.

Not quite the same scenario,

I recently registered an import and the v5 came back with my name spelt wrongly, I just sent it back with a covering note, it came back corrected.

As above, I'd write to them with the correction request. No reason for them not to do it for you.

I have epilepsy and much experience with the DVLA in that respect. I do everything in writing to them and send it signed for service. Always gets a response. Their response time can be up to 8 weeks though.