As far as I can remember, the fins (in fact Aerials I was told) were part of the probe mod. When aircraft went in for their next major service, (I do not know which), the fins were replace by the larger aerials and the refuelling pipes (2 of) than ran down the inside of the fuselage (Yes, as used on the bowsers) were replaced by proper fuel lines in the bombay. Although the original mod was a bit gash looking, the pipe was very robust with many an item dropped on it and it never gave off any fumes.
LORAL was another name for the Yellowgate ESM, (I believe the manufactures name) and was a major MOD fit, the fins had nothing to do with it, I believe they were replaced at the same time. LORAN was a navaid that was on the MR1 and was removed from the MR2 when GPS was added, (I think), or when the ground stations were taken off the air.
All that from a wettie, so some details may be wrong.