IT has to be one of the better assignments for the boys from Glasgow. Two days of top-class rugby, played out before fanatics in one of the most famous tournaments in the world. Yes, it won't be bad, Major Angus MacDonald, of the 1st Battalion Black Watch (Royal Highland Regiment) agreed, as some of his 220 volunteer stewards gave their new red T-shirts a muscle-flexing workout for duties at the Cathay Pacific Hongkong Bank Invitation Sevens this weekend. ''We were enthusiastic in volunteering, not just to be stewards but to watch the games,'' one of the volunteers said. ''The Scottish team will be playing, you know.'' We do know, but we also know something else. That 20 years ago, when the regiment was last stationed in Hongkong, the refrain ''The Black Watch is coming'' struck fear deep into the heart of Wan Chai. ''Oh, some of them were terrible,'' said a source who can still remember those days. They would fight at the drop of a hat. There were always fights breaking out in bars like the Popeye, the California and the ABC. They were the big three then. ''This time around, it all sounds very dull. They haven't closed any bars. Nobody's been arrested that we have heard about. Probably most of them were born after the regiment left last time.'' Major MacDonald agrees. This time around, his men have been very good indeed, and there is no reason to assume that this weekend will be any different. ''We are diplomats,'' he said of his strapping crew-cut troops. ''We, as a battalion, looked after the Commonwealth Games in Edinburgh in 1986. Of course, many of the soldiers here may not have been there, but some of the commanders were, and they have the experience. ''I am certainly unaware of the battalion having a reputation of being rough. We have been here since January and I am not aware of any incidents so far to warrant that sort of description. Whatever happened, happened 20 years ago. It has been at least two generations since then.'' And as a tradition (even though it has only been practised over the past three or four years) soldiers from the British regiment at Stanley Fort have been recruited as stewards to help keep spectators in line. This year in particular, organisers are anxious to ensure there will be proper crowd control at the new Hongkong Stadium in the wake of the Lan Kwai Fong tragedy. Organisers have actually gone as far as introducing light beers to encourage excited fans to ease off alcohol. New guidelines introduced by the Hongkong Rugby Football Union have restricted the four beer suppliers to 20 waitresses selling beer at any onetime - a stark contrast to last year's practice where one brewery alone employed 170 women. In their bright red T-shirts, the stewards will be deployed at 12 different sections around the stadium at all levels to guide and control the 30,000 plus crowd. This weekend, Major MacDonald said, the main duty of stewards is to assist fans and their families to navigate their way to seats, and then leave them to enjoy the event. ''You can say we will stay in the background but there will be those posted at ground level to stop people from invading the pitch,'' he said. Stewards have also been instructed to remove from the stadium anyone ''who is under the influence of alcohol to the extent that it affects their judgement or control at the tournament.'' Major MacDonald said it will not be a problem if people simply get merry and enjoy themselves without being a nuisance. But he warned: ''If they cause disturbances to the public, they will be escorted out of the stadium by both the stewards and the police.'' Stewards will be strategically allocated in the stadium which the force has divided into three sections: the ground level, middle level and the top concourse. ''We have segmented the stadium into sections so we can control the divided crowd by allocating each area with an officer and a number of stewards,'' said Major MacDonald. He said there was no need for any training prior to the event and it will be a matter of ''do our job there and then.''