"Worth" is up to you. You have a 3/4 ton truck, which aren't as popular for rodders and restorers. Hence the availability of 1/2ton parts vs 3/4ton parts. The good news is, the 54 will have the latter brakes (bendix) which are available through the suppliers listed here.
The bad news is your rear end will probably be a 4.57 ratio, and replacement gearsets are not available. If it is the original Eaton HO52 axle, the center section can be swapped easily with a later unit. Some 67-72 3/4tons with automatics had a 4.10 ratio, but they are hard to find. Getting another 8-lug axle the right width with a decent ratio is also difficult.
If you want a faster axle and don't mind going 1/2ton (you thought you had one anyway), you could find a 6-lug axle for the back and find a 1/2ton beam axle from someone here who is switching to IFS. You'd have the equivalent of a 3200 (sort-of).
Good luck, have fun and remember, it's YOUR truck.
Current fleet (subject to change w/o notice) \'49 GMC 3/4-Ton , 60 Austin Healey Frog-eye Sprite (some assembly required), 2011 Dodge Avenger, 2015 Jeep Cherokee. No, they don't all run. My other ride is a (B737)no, (B767)no, A320.... Update... was Embraer E190, now Boeing B787. Knowledge is a wonderful thing, but ignorance means you don't know you can't do something.
| 
