Try the Search facility in the top rh corner.
This was the latest discussion
http://www.periodproperty.co.uk/forum/viewtopic.php?f=1&t=16260
The trick will be finding someone in your area.
Failing that, plastic media blasting can do the job without damaging the beams. Some companies will travel quite widely.
If you edit your Profile to show your location that may help in obtaining recommendations.
Yes, with outstanding results. However, just saying that triggers some people around here, so if you want details, perhaps drop me a PM. It's always handy to give your location so that people can recommend local suppliers/ contractors.
Alternatively, Mr G could simply post his miracle workers details out here on the open forum so we all, including me, could try them out, but whatever.
Maybe Marlene would be so kind as to post details of the company if she is able to go ahead and use them and obtain similarly pleasing results, that would be most helpful.