4l80e Driveshaft Conversion Question

[Step'67]

Question for any that can answer, I am in the process of converting my sm-420 to a 2006 4l80e. When I purchased the transmission it came with a slip yoke, and of course the stock one on the 420 is the fixed, bolt on style. This is the only thing holding us up, converting the driveshaft. Now I know that I have to get the shaft shortened, but if I am to keep the rest of the driveline, how am I to go about mating the 4l80e to the stock driveline. Because of the carrier bearing and the crossmember it mounts to, there isn't any room to use a slip yoke. Are there bolt on yokes available for these transmissions anywhere? Or should I just drop some cash and really give the driveline guy something to think about? I'd prefer not to convert it to a one piece because of the associated cost. Here is a picture another member posted of the same driveline I am dealing with just for visual reference, the right hand going to the transmission, the left to the rear end, and a slip yoke in between.