I will take a stab Mike. The 230 is the same series as the 250 and 292 engines. I believe that you can use the same tranny, but you have to go to the v-8 bell housing. I believe that the 41-46 has the clutch and brake attached to the bell housing, so that has to be considered. My personal opinion is that if I were going to upgrade to something that required a different bell housing, etc, I would just go ahead and replace the non-sycnro tranny and get something like a t-5 with overdrive, or at least a 60 model 4 speed thats set up with an open driveshaft. This would give you a stock looking truck with a more modern driveline and better rear end options.
Ralph
