Hello!
This is my first 1:48 model. I decided to upgrade it with Aber PE fenders and basic set. Also will change the tracks for Friulmodel because Tamiya provided inappropriate model of trucks with full teeth for this early Stug. I started the work from soldering the fenders. Here is some SBS photos.
I use ceramic plate, KOKI soldering paste, gas torch, 'TAC' and clamp tweezers. 
I place the bent element of the bracket in the clamp tweezers, the tweezers in the handle and I settle the wire (imitating rod) in to ball of 'TAC'. I establish the 90* angle and put on the drop of the soldering paste.
Next i solder it together with gas torch.
Done!
Then I put on the drops of the paste under the elements of joining.
I lie down small elements on the drops of the paste gently and level so as they should be.
The next layer of the paste which will connect elements with the rod of the girder.
I gently put earlier made element on place.
I squeeze the whole with the clamp tweezers.
It's better to place the element of the bracket in the ball of the 'TAC' to protect him before fall away during soldering.
We have strong joining after the second. 
The soldered on girder.
I cut off the rod under proper angle.
And polish with file.