I finally cleaned out the garage enough to try this, and it looks promising, but not yet perfect. I've got a 1995 Dodge NV4500. Has a 23 spline male output shaft with 6 hole circular bolt pattern. I'm trying to bolt it to a 1975 Dodge NP203, with 23 spline female input, and Dodge oval bolt pattern. If I can get the two parts to fit together I can drill the 203 to match the circle bolt pattern, but here's the tricky part: The cap screws holding the input bearing on the 203 don't have enough clearance in the NV4500 tcase adapter, and they bottom out. A quick look at the old adapter shows a much deeper machined area in the cast iron. 1) Can I clearance the new aluminum adapter without weakening it? 2) When drilling for the new bolt pattern, there won't be a boss inside the 203 case at the correct spots. Is the standard 203 case thick enough to hold the mounting bolts? 3) Careful with this one, highly technical terms here. Should I make a cover for the other shaft "thingy" on the 203. It's the one that sticks out towards the front, looks like the shaft for the other gears in the range box. The original adapter covered it up and it looks like I will have to also. Would a suitable piece hacked off the old adapter work OK?