Chris,
What you presented is a question that is open to many subjective opinions. It all depends on what you are trying to accomplish.
The first thing to consider is that it is going to have a 5 lug bolt pattern which does not match the front unless you are planning a 5 bolt disc brake conversion. It will also require welding the spring pads and possibly a u-joint change. Wheels will also be required. In addition the gear ratio may not be a good match for your existing engine/transmission combination. If everything is being changed out then it may be a good choice.
If you are going to leave everything else stock and need better highway performance, put in the factory overdrive transmission.
It's cheaper, less work, and no modifications required.
Fred

Last edited by rfs56trk; 12/04/2014 5:56 PM.

1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine