Hi Mike,
At least in TM 6.5 the "scripts" directory includes a script called NumGrad. It prints out a short documentation with NumGrad -help. It seems that it can also be combined with jobex (jobex -level NumGrad). I did a quick test at HF level and it seems to work OK (runs without crashing, that is). I have no idea why it isn't mentioned in the manual, maybe because it's a rather new addition.
Best,
Antti