well, Precision is full of it (ask 'em how many race cars they have that are using a 67gtq.....)
first of all, any GTQ turbo will not work on a "stock" motor
with a built motor, 38-4000 stall may do it
a 67gtq is an all out race turbo.......not for a mild build
if you intend on using your car on the street, get something else (TA-49, 60, TE-44)
if you are looking toward low 10's......get the 67GTQ