7 1/4 rebuild advise

About the only special tool you will need is a good torque wrench. If you plan on re using the ring and pinion in the 7.25 be sure to use the yellow gear paste and check the gear mesh. Take photos as you will want to put it back like it was. Also check the gear lash prior to disassembly and get it back like it was or as close as possible.
If you are putting in new gears you can check the existing mesh just to see what they were, but you will set the new gears up as new.
Prior to taking it all apart, you should verify that the bearings and seals and other parts needed are available.
Good luck, you learn a lot by doing what you are doing.