Re the peaks.
On the Proflex this peak is fitted with 3 push types fittings that go through 3 holes that were already in the frames. In the E-flex the proper peaks clip into 2 side parts and then theres 2 other clips that go into the top slatted area of the eflex frames.
I think that you should be able to stick a JT peak onto the elex and use the existing holes, but as you will note the eflex have the slatted tops whereas proflex are all holes and whilst you could just push this in, as its not secure it could pop off.
I hope this makes sense - it sort of did as I typed it !!