Hi manna, just picked up this thread. I was found to be breech at 36 weeks, with dd2 (3rd baby).
I tried the lot reflexology, acupuncture (burning smellly stuff on your toes), chiropractic (Websters technique). Hate to say, none of it worked apparently all these techniques work better before 35 weeks, as there's more room to turn. Like you I'm 6 foot and have had big babies, tho' not as big as yours (respect!)
Had ECV at 37 weeks at University College Hospital in London. Everybody'd told me horror stories about it, but in fact it was fine. They put you on a drip of adrenaliney like drug which is ok at first, but does get unpleasant after about one and a half hours, as it makes your heart race and makes you very shaky. The drip is to relax the muscles of your uterus.
When it's taken effect they get two people to come and do the turning, with lots of checking on the ultrasound. One gets their hands under the baby's bum and lifts it out of your pelvis, the other pushes behind the head and they try to persuade it into a forward somersault. It is uncomfortable, particularly at the point where the baby is horizonal to you, but not agony, and it was over very quickly (couple of minutes). They turn the drip off, you feel much better v. quickly, and after an hour of monitoring, off you go home, feeling much more comfy without a great hard head under your ribs.
I was told lots of misleading stuff about ECV which you've probably heard as well (the baby can turn back, it's agony, the placenta can come away etc.) so here are the statistics as UCH told me: (a) the overall success rate is 50% in getting the baby to turn, but much higher in 2nd and subsequent pregnancies (lack of muscle tone, don't you know!) (b) less than 1% of babies turn back again (c) At UCH they do a couple of ECV's per week, and the last time they had to do an emergency c-section was four years ago.
It might be worth checking how experienced the people performing your ECV will be, as it seems to be an art as much as a science, and what the success statistics for your unit are.
In the same situation I would do it again without hesitation. Dd2 was born three weeks later, 9lb 5oz. She's now three and a half months and happy as larry.
Good luck, and keep us updated! Post again if you have any Qs -- I'll keep checking.