Hello, I have a 71 Riviera with the original transmission with 103K on it. leaks a little from sitting (been trying to drive it more). I have a 72 Riviera with original transmission and only 73K on it and it has been sitting for 6 years. I will be swapping out components to convert the 71 from column shift to the 72's console shift. My question is, would it better to rebuild the 72's with lower miles and swap it along with the linkage or just keep using the 71's original transmission and swap the linkage only? Or reuse the original and just have it rebuilt? Thanks for any advice.