the v6 and the v8 use the same motor mounts---we have put a 5.2 in the spot the 3.9 fit----also the motor mount ears actually unbolt off the frame---i have saved several sets and have just recently handed a couple to a friend so he could use them mounting a 5.7 hemi in his 34 plymouth coupe----the gen 1 dakota is just fine for the job at hand--i would watch for a single cab short or long bed.....