Don't throw out those 3.73's, within a week you will be trying to put them back in.
With no heads the car will feel like a slug if you go down to 3.27's.
3.55's aren't worth the work to switch from 3.73's, so your options are limited.
I agree, ...with the 3.27`s in my 98 GT, you had to slip the clutch to get it to move. I swamped in a set of 3.90`s and the tach only went up 500 Rpms at 75 mph. My 05 has 4.10`s and as a musclecar, 2500 ROMs ain`t squat when you look at the infamous 69 Boss 302 with a 3 SPD auto or 4 SPD with factory 4.10s.......redline is at 6k or above, don't get ricer phobia.