The GM NV 3500 and 4500 tranny's I have seen used a one piece tranny and clutch housing.These models should bolt right up to a 230-292 engine. The speedo,clutch linkage and perhaps some other details will have to be worked out.The 3500 model is found in 4.3 S10's,is rated at 300 foot lbs of torque.The heavier 4500 model is rated at 410 foot lbs of torque.You might consider the 3500, its probably less expensive and the shifter may be in a better location for an older truck. Try tis link for info...
http://www.newventuregear.com/transmissions.html
