Neither of those transmissions is ideal for your car. The NP trunk trans is not what you want. The 2wd 1/2 ton trucks and vans came with b-body length overdrive 833's. The a-body 833 uses a shorter tail shaft and positions the shifter wrong for your car. If yo uran the short tail transmission you would also have to get a longer driveshaft where the b/e/od truck 833 will use your stock 727 driveshaft. I think trans mount would need to be customized a bit to run the short tail trans in your car as well. If it's an 18 spline (doubt it but could be) then it would be worth converting over. If it's 23 spline just keep looking.