If there's no part time conversion installed, you don't want locking hubs of any kind. Some hubs are "auto-locking" where they lock in automatically when the driveshaft turns, and also can be locked solid. Leave them locked, or better yet, remove them and replace with the factory slugs.
If you unlock locking hubs on a Quadratrac Jeep, and switch the glove box control to normal operation (rather than "emergency drive"), you will ruin the transfer case. There are no replacement parts to fix these any more - you'd have to hope you can find enough good used parts to put a working TC together.
You might be lucky, and the TC is permanently stuck in "emergency drive." Then, you could go 2WD using locking hubs. But that's another bone-head scenario.
No locking hubs on a factory Quadratrac. Bad, bad, bad idea. Very dangerous to the car's health.
Ask the owner to demonstrate the car in full-time on pavement, hubs fully locked. And make sure the switch in the glove box works - you should notice 4WD bind-up on pavement with it locked in to "emergency drive," and the binding should go away in normal mode. Always with those dangerous hubs fully locked.
BTW - towing a full-time QT Jeep with two wheels on the ground and two in the air will also ruin the transfer case. Clutches will be worn out, TC killed very dead.
1) '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS, hubcaps. 2) '82 J20 360/T18/NP208/3.73, KOs, 7600 GVWR 3) '75 CJ-6, 304/T15, PS, BFG KM2s, soft top 4) '95 VW Golf Sport 2000cc 2D