K-10 drivetrain ?

[gmtruck71]

My 71 K-10 has 3.07:1 gears. The rear has failed and I would like to replace with something higher such as 3.42 or 3.55. The rear is 12 bolt GM the front is Dana 44. Cannot find 3.54 or 3.55 for the rear, and cannot find 3.42 for the front. I can only find 3.73s or the 3.07s for both front and rear. Has anyone done this, and is there any later models that will fit under the chasis without any modifications. Does anyone have 3.73s front and rear complete housings with rear posi? Thanks for your time.