Regarding FM Immunity, it looks as if the previous wording has been revoked and this wording issued:
http://www.caa.co.uk/docs/224/srg_ga...mune%20GE4.pdf
My reading is that wording for a/c < 5700kg, non FM comms are not an issue, but non-FM ILS/VOR are restricted to VFR only regardless of airspace. Non-public transport flights may have only a single non-FM immune ILS/VOR in CAS. Therefore, as there are no requirements to carry radio nav aids in Class G, the CAA would prefer you to DR in IMC! However, the implication is that you can use your non-FM immune VOR in uncontrolled airspace because the authority can never doubt otherwise.
AIC Pink 87 is very badly worded. It suggests that even non FM Comms in any aircraft must be placarded and limited to VFR only and it refers to a long time defunt AN 84.