IMHO brakes are just one of many problems you will run into. I have a Camaro rear end my 1954 1/2 ton. First off the Camaro rear end is only 1" wider than the original; seems to me the full size Blazer is way too wide. These are the problems that had to be addressed:
Mounting - spring spacing and mounting is different so I used springs from S10 Blazer and fabricated new spring mounts.
Shocks - required fabrication of new mounts.
Drive shaft - convert from torque tube to open configuration. Used cut down two piece from late 60's truck and fabricated steady bearing mount.
Transmission - replaced transmission designed for torque tube with one designed for open driveshaft.
emergency brakes - use Camaro cables, had to make mounts and connections to existing e brake cross shaft.
service brakes - changed to dual master cylinder and added booster (not required, but nice to have)
Front brakes - installed disc brakes on front - now all 4 wheels using same 5 bolt pattern.
Proportioning valve - need this with disc/drum setup. Used one from a 1/2 ton pickup.
Back to your original question - it should work as the brakes themselves are probably not all that different. I think that the Blazer has 2" wide shoes in an 11" drum and the old truck 1 3/4" shoes in an 11 drum. The old truck has 1" cylinders - don't know what the Blazer has. You may have to install an adjustable proportioning valve.
