I’m post photos of my finished 2Stroke head, one of them clearly shows the heater circuit. Note that it is a tightly twisted part going from the 2 100ohm resistors to V2 and then V1. Note that in the DH book right next to Pin 4 & 5, it’s says 6.3v. The heater wiring needs to be away from the other wiring in the amp and tightly twisted.
The other twisted wiring in my amps is just to keep things neat and organized. Only the heater circuit requires the twisted pair for noise cancellation. This is the same concept of noise cancellation that happens with a humbucker pickup.
Refer to the wiring schematic that came with your PT, if you didn’t receive one, go to the Weber website and check it out there. I think the Weber transformer has a center tap for the 6.3v taps but if not, add the 100ohm resistors. Don’t add the resistors if there is a center tap. Also, there is a center tap for the B+ (high voltage) taps that go to the rectifier, that goes to ground too. If the PT includes any other center taps (like one for the 5v taps) DO NOT wire those to ground, just cap it off with heat-shrink tubing or tape and tuck it out of the way. Transformer manufactures sometime change the color of the leads, so it best to get the info directly from them.
Read more about where to wire the different grounds in the amp for maximum noise elimination in the posts here on the TAN site.