So, after a discussion on the Rubicon Models forum, and purchasing some 0.7mm brass rod, I went about replacing the lift rings on the glacis.
First I cut off the strange moulded "handrail".
Then I drilled two holes, one at the top of the "handrail", the other at the bottom.
Unfortunately I used a 1mm drill (intending to use 1mm brass rod). With the tools available I was unable to achieve a suitable ben in 1mm rod, but managed it with 0.7mm rod.
If I had started this before assembling the kit, I would have used the handrail jig (an etched brass sheet with holes for bending model railway handles - for 28mm models I tend to use the 7mm scale jig).
On the bright side, it did mean it was easier to get the lifting ring into the holes ^___^.
Having fitted the ring, I then used liquid poly to fix it in place, applying it to the ring so it would flow down and fill the hole (but possibly the ring as well).
On the plus side, it did not flow all over the glacis.