Remember the explorer axle has the 31 spline axles, most rangers are 28 splined with a few exceptions. I took the 8.8 plunge no regrets. https://www.forabodiesonly.com/mopar/posts/1972221357/
You have to consider a gen2 barracuda or a duster can accommodate a slightly wider rear end than a dart.I have a Ford explorer 8.8 with a limited slip differential. I'm gonna do the swap at some point. I have heard of a few people claiming that they have done it directly without cutting the long tube down been iv never actually seen proof. I would think even if it would work you would have to have some funky offset wheels to make it work. IIRC there was a member here who did the swap without cutting it in a barracuda.
I agree RRR, I see no point in you swapping to 8.8 if you have to redrill the drums. I think the 7 1/4 will hold up just fine.