Replacing a radiator - radiator valve tails

[fudokai]

An old radiator in the hall rusted through and leaked so I'm replacing it with a new (Stelrad K1 - single) long, low radiator.
The rad arrived the other day and I'm trying to fit it but I'm stuck on the radiator valve tails.
I've removed and replaced radiators for decorating before and didn't anticipate any major problems but ...
The instructions say "Prepare radiator valve tails with PTFE tape and fit to bottom radiator connections".
The bottom radiator connections are plugged with something which looks like it takes an enormous phillips screwdriver or similar. I've tried moving them with a bodge tool but they don't move easily and I'm afraid of damaging something.
Do these things come out? Do I need a special tool? Do I need special valve tails?
SWMBO is giving me that look that says "you said this would only take a couple of hours and now ..."

Alan

 

[seco services]

they are only plastic caps to protect the ends.
just use a large screwdriver. they will come out.

 

[weareleeds]

Dont try to prize them out as they are screwed

 

[fudokai]

Thanks,

I thought at least one of my screwdivers would get them but eventually I used the end of a bicycle bottom bracket spanner.

The real problem was that the instructions didn't say they came out nor could I see a join and my first attempts at unscrewing didn't move them but just went CRACK!

Alan