i have a 1980 gmc 4x4.My truck has a 10 bolt front and
a 12 bolt rear.I want to put lockers front and rear. I
was thinking about buying some lock right lockers by powertrax,but they only have them for a 10 bolt and not a 12 any suggestions on what i should do thanks.  

As I have said before, locking the front axle with anything other than a manually selectable locker is a very bad idea. The replacement lockers you suggest DO NOT have the ability to ever power wheels on differing speeds in a turn so you can have guiding problems because either wheels will not be able to maintain proper ground contact because they are forced to turn same speed even though they are on different rolling radius in a turn and/or you will get tight steering and steering wheel whip as wheels try to go straight. Also Ujoint are not constant velocity and in turns they speed up and slow down twice per rev complicating matters. Spider gears in open diffs and even LSD's can cope with this somewhat but a replacement locker cannot. Makers of replacement lockers never really bother to tell you this nor do they tell you that they CANNOT power both wheels at differing speed in a turn. It is 1wd with one wheel coasting when under little or no power in a turn or both tires powered at same speed.