Here are the documents I use for determining What a Tanker! stats for Quar tractors.
Approaches to conversion:
https://docs.google.com/document/d/1zsKUYY9hnsx0pl_pRuRQp9-kiuecP0bj_Ig3TQV8RHw
Stats for the tractors I use:
https://docs.google.com/document/d/1_jraKuyJTe07xj7cb-pKcGuohrtylWUzkh1ZJE3Bn_w
You can see some of my battle reports on this blog.
I have not evaluated the stats for a preview of the next version of This Quar’s War, so some of these tractors may need updates.
I use a point system from Herkybird, who came up with the system after coming to the conclusion that smaller tanks in What a Tanker! needed to be cheaper compared to the more powerful ones.