Nick, I assume u are going to fab a bearing retainer for the rear that will also support the input shaft of the trans. The thing I would worry about is the overall mass of the shaft and joints, if they have too much kinetic energy it will be a bear to speed shift and the syncros won't last as long.
U got any pics to share? I have a bellhousing from a c6z06 (for templat/measure) but I would build off of a stock vette torq tube. The 97-04 tubes are longer than 05-up, and the 6sp bellhousing has more height than the auto bell. My point is that by mixing u can vary the over-all length of assembly by several inches without having to shorten-lenghten the tube and shaft.
Do u have a measurement from back of bellhousing to mounting face of tranny?
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