Private number plate question

[Fats25]

My wife is going to put her private plate on her car tomorrow. Fortunately for us, we have one of those mini dvla places near us, so she will head down (like I did earlier this year) with her V5 (in her name), V750 certificate of entitlement, and her tax disc. Should all be straight forward.

However I bought her the plate - so I am the purchaser, and she is the nominee.

According to the V750 the purchaser needs to sign the V750. However it does not state if I have to then do the paperwork at the dvla or whether I can sign now, and she can then take all the paperwork and do the rest in person herself.

Anyone done this and can confirm she can go with my signature on the V750 with no issues?