here a review of the book i think thunder is on about?
http://pmms.webace.com.au/reviews/books/allied-axis/a-a03.htm
but this might be good too
http://ipmslondon.tripod.com/armourreviews/id29.html
the Armoured M26 was used in ww2 but was slowly replaced by the unarmoured M26 toward the end of WW2,
so you can pick anything in ww2 for it to pull
ive seen photos of a M26 towing a Panther with the Panthers tracks off, and that was at the M26s limit so the M60 would be a bit hard
they were used in the middle east after the war