[A1971Blazer]

You can go the opposite way (higher ratio to lower ratio) with a special "thick" ring gear, but you can't go lower to higher without a carrier change.
The pinion gear diameter is much larger on a 3.07 than it is on a 3.73+, therefore the ring gear has to be further away initially.
You could swap in an OD transmission and keep the "fun" gear.....but it would be more involved/expensive.