Brake Boosters explained

[ozbox]

HQ..double prong adjustable straight shaft..
HQ..double prong non adjustable straight shaft..
HJ..double prong non adjustable straight shaft..
all 6 cylinder and v8 are the same interchangeable boosters in hq and hj.

HX..HZ..bent shaft single circle mount to pedal 6 cylinder and 8 cylinder drum brake rear..
HX..HZ..double diaphragm disc brake rear booster..

WB..bent shaft same as hx hz but booster will not take early pbr master..
WB STATESMAN..double diaphram for disc rear..master cylinder looks the same as wb commercial but is not interchangeable with drum rear.

6 that i can think of..

HQ HJ does not interchange with HX HZ and vice versa because of the pedals and the shafts..angle of push isnt right and brakes wont work properly..
wb will interchange with HX HZ and vice versa but wb has metric brake lines to the master cylinder..

sorry to steal your post adam but you were too slow and it was raining here so i just went and did it...