Hi,
I have an 1983 Z-28 T-5 with the .72 overdrive and I have a 3:55 10 bolt and have no problems at any speed. Yes, 1st gear is short, but I do not understand why you wouldn't use it. If you are cruising on the highway, a 3:55 rear with the .72 OD is perfect. Perhaps you need to add a little HP to your motor to prevent the lugging in 5th gear. I do have the 292 in front of my T-5 and it has a bit more torque than your 195. I'd say keep the set up you have and add 2x1 intake.
RapRap
1940 ChoppedChevyCoupe
PS-Look for a 250 for a great swap for your wagon.
