The trooper rad is a 3 row rad and if it is in good shape with the correct fan shroud i would think it would cool it , i used that same rad in a trooper with a 4.3 chevy and an automatic trans and never had a prob, with cooling, from the looks of the eng mts in the photos this eng came from a trooper with the front bracket that overhang the the frame mts, i have been doing a lot of measuring with those mts and if you remove the cushions and replace them with the 4 cyl gas cushion i think you may be surprised at how close they come to the orig , frt and rear bolt holes on the trooper frt frame mts , from what i could measure they would come within a 1/4 inch of fitting , the reason behind this thinking is the trooper in japan and parts of europe is available or was with the 2.6 eng up untill at least 1998 ,very doubful the frame are that much diff, trans mts should be very close , something you might want to consider is the clutch setup i have done 2 coversions on the mua trans which is what you have, and changed them over to the cable operated setup by using the early throwout arm and release bearing, takes about 2 hrs to convert it over and it (or rather they) have been working great for over 2 years now , one in an 87 with the mua and one in an 89 with a turbo dsl conv, be glad to explain how i did the conv, if interested Jerry