Sorry about the first post on the site. But I have been hovering around this site for a while. I am the builder/owner of the E-Vade/s. I have the Albins Gearboxes in my cars. I am absolutely sold on them. I am not sure if they will fit in a GT40 arrangement. But if you look at my car you can see that I don't exactly have a very long engine bay. (
www.evade.com.au)
Their sequential AGB10 has happily handled the abuse that I have pushed through it. As you said their workmanship is second to only their customer service.
Sure they aren't cheap, but I look back on the amount of money that I have spent on trying to get a UN1 to handle the horsepower, and it really becomes a very cheap exercise.
Oh, before I forget I am not on the payroll. I am A naval engineer, (not to be confused with Rob Logan, yes I know of him, but don't know him), that just decide with the wife to build my own car. Then did another.
Regards Dave Walter