I checked the factory set torque on two new TT46PRO engines tonight. The head bolts were all in the 12 to 14 "lb range and the backplate bolts were around 6 to 7 "lbs. I've had a head bolt strip at these settings.

At least I'm getting adept at installing Helicoil thread inserts with all the threads I've stripped lately.

I am now using 10mm cap screws with Dave Shadell's backplate mount on the TT. The factory bolts are only 7.5mm long.