That is as close as you are going to get with a 46RH. I honestly don't know how that would hold up in his application though. The billet cover and lockup clutch take up room in the converter that the turbine, stator and impeller occupy so all those components have to be smaller, which equals weaker. It's one of the reasons high horsepower automatic drag cars use GM transmissions, the bell housing is deeper.
You could of course have someone build a special one off converter (expensive) and space the trans back but then the crossmember needs to be moved and the driveshaft shortened. Maybe not a big deal in Ray's case but is in others. I had to do that when I converted my '92 diesel to a lockup. Everything had to move rearward 1.250".