DFC Value

Hi guys

I have an original DFC to a Lancaster pilot, in fact I have his uniform, log book and photo album, all given to me by his wife some years ago.
Les Dale, 103 & 550 squadron was not one for wearing his medals nor attending events, his DFC is still in its un mounted condition in its box of issue.

My question is this, I feel that I would like to get his DFC engraved, I would worry that if it ever left my hands it could get parted from any related information and become ‘unknown’.

If I were to have his name engraved and the date it was awarded ( it was an immediate award) on the reverse, would this detract from its value ?

Any advise ?

Regards

Jules