Hi Snuffles, not a problem, this Covid has put everything off tilt, what seems like an hour turns out to be about six, lol.
I used to arrange these up to about ten years ago? so lost contact with most of the guys.
I arranged them around what the couple wanted so they dictated how many guys they wanted (As it happens I may be setting up another group as just before the Covid started I was contacted by a couple looking to have a five man gb and wondered if I could get the guys).
And yes you're right, slow and steady, took me a while to get the right guys but I had the advantage of helping out at a swingers club/adult events, although I had about twelve to fourteen guys only once or twice did I use them all at once, most couples wanted three or four to start of with.
At the club couples would phone asking to set them up and we'd inform our regulars that a couple were/might be coming and may want a gb (At the end of the day nothing was guarenteed and the couple had to feel at ease), if they tuned up we'd go through the ground rules and what their limits were, they could choose how they wanted and if all ws well we'd sort a place for them to have their fun and there'd be someone on the door to stop anyone else getting in unless invited.