I try not to join in threads about identifying Lejeune frames because they are notoriously difficult to call, but there are a few observations that I think should be made about Chris' frame.
The shots of the full frame do make the frame look like the Lejeunes that we readily recognise, and the first detailed photo shows the long oval overlapping top-eye plates so typical of the Lejeunes built by Bernard Carre's team of builders, but they do not have Carre's name on them...as so many others didn't.
The joints between the rear stays and the drop-outs are very non-Carre and non-French, as Lynn has pointed out ie they are not scolloped out. Whereas the cable eye for the derailleur cable on the R/H seat stay is very Lejeune and very Carre, as is the Wagner fork crown, but the brake bridge is not...definitely not..nor do the bottle bosses with their diamond back plates look correct..and certainly not the brake cable eyes...nor perhaps the Campagnolo gear lever bosses.
The other real oddity about the frame is the bracket shell which looks remarkably similar to a Nervex Pro one...but is slightly different..possibly the metal curlicues have been lightly refined with the stroke of a file...but the lugs have not received any tidying up of their stamped profiles...and it was not in the nature of Carre's workmen to tidy up lugs'profiles even on the frames built for the Pros.
Finally the ends of the front forks do not match the ends of the rear stays..not unusual really, but the forks obviously had had domed ends filed flat..and it appears that the rear stays were cut straight 'in the box'..
I have a Lejeune frame from no later than 1972...finished in the familiar red enamel with light blue panels ...the former Sauvage Lejeune colours.The frame used to belong to the quite well known and successful French Pro Bernard Guyot and is as ridden by him.. totally original. The frame has white transfers on the down tube like Chris' frame and it has the same head-tube transfer with the heart incorporated. But that is as far as any similarity goes except for the Wagner crown, Reynolds tubing and Campag drop-outs. The lugs are the short and curly 62B ( I think that's the correct number). I also have a Lejeune track frame..in the familiar red enamel with the same white lettering on the down tube, same top-eyes aas Chris' same lugs, but different bracket..but with the full word LEJEUNE on the head-tube..it dates from the very early 80s
I think that Chris' frame is later than the Guyot one by quite a few years..late 70s maybe even early 80s like the track frame but as to which model it might be...I really haven't a clue..and will be happy to let Lynn to sort out that matter.
Norris Lockley
Settle UK