Don't start! I'm quite sure the supplied t-wrench is good enough. I'be been using them for years. Happy to be disproven though and I have a spare I can send you to check...
Every once in a while we get a torque wench that slightly under or over calibrated, (former is more common), especially after it been used for quite a while, or not used properly (never reset it to zero when not in use).
Don't start! I'm quite sure the supplied t-wrench is good enough. I'be been using them for years. Happy to be disproven though and I have a spare I can send you to check...