I was in a pretty similar position once.
I bought a shiny new civilian professional logbook, copied the flights up, and tucked the completed pages of my tatty military logbook in the back, which contained all of the relevant signatures. They're all still there, and CAA who have seen my logbook more times than I care to count, have never batted an eyelid at the method. If you'd rather just keep your RAF logbook intact on the shelf, tuck photocopies of the relevant pages in the back instead.
With regard to bose-X's statements about gliding and AEF not counting - he's right so far as issue of a civil powered licence is concerned, but for interviews, etc. where you might want to demonstrate your total flying experience (and just for personal record) it's probably worth copying them up - just recycle two spare columns for the glider and passenger (AEF) hours, so that it's clear that you aren't claiming those hours for issue of a PPL(SEP), CPL(A), etc. (It's easy enough to make up stickers on your PC to relabel the columns of a logbook - I do this also, since my flying falls into more separate categories than most peoples I need to).
G