I was thinking of putting it in the 1/2 Cab. What all is involved in doing this? Is this going to change the drive shaft length?
also need advise on what to put in it as far as gears/locker good quality and that hold up real well.
still need front gears, front axle shafts. I have ball joints and seals.

It's pretty easy-the axle itself is bolt in if you're using a EB housing. It shouldn't change the driveshaft length. If anything, it'll make it fit better if you're lifted and still running a stock lenght. Re: gears and lockers, it depends on your goals. There isn't a huge difference between gears, as there aren't that many factories making them. It's mostly differences in how noisy they are and maybe minor differences in strength. How hard are you going to be wheeling this rig, what size tires, will it be street-driven, etc?

I've been advised to avoid used gears for rear axles. Since they are the driven axle on the highway, used gears in rears are frequently noisy. Since the trucks aren't frequently driven at highway speeds in 4 wheel drive, you can get away with used/cheaper gears in the front end. But I also read that many have had very good results with some of the cheaper brands of gears (front & rear), with a good set up. USA Standard are Yukon gear "B"s, but perform well.

Something I found recently, don't buy from ringpinion.com. They are a common source in the 4x4 community, but there are much better deals to be found. I am looking at new ring & pinon for my 10.5 Sterling, and I found a place selling gears & bearing kits for about 70% the price of ringpinion.com.

Your gear ratio choice depends on lots of factors. Motor, transmission, tire size, expected use (and maybe future upgrades). If your truck will be highway driven, then it really boils down to making sure you are running on the highway at an RPM your motor likes. Most our 302s are good around 2500-2700, with good power on demand. I'm running pretty low at about 2400, and its a pig to get up hills or pass. I used to run at 2700 with 4.10s and it felt a little high, for my taste, but lots of trucks are running that way.

I've been looking into this recently myself, and found Dana SVL ring and pinion gears, they are Dana's own high end line made for the aftermarket and quite reasonably priced.

Unfortunately they don't make any Ford 9 inch gears lower than 4.56 (yet)

I have USA standards in my 79 front and rear. They are quiet when set-up properly.

I'm going to move this to the Tech section. Hopefully you'll get more eyes on it.

You can change the ring & pinon, but you'll either need a "thick" set of 4.11s or you'll need to change the carrier too. D44s use one carrier for gears 3.73 and down, and another for 3.92 and up. Thick gears allow the 3.92 & up gears to be used with a 3.73 & down carrier.

What transmission do you have?
If an overdrive you should look at 4.56 up.

Thick gears?
Could also be an excuse to build it Jana K4 style, if you want more strength.
Bigger diameter gears, larger pinion shaft.

Thick gear:
http://shop.broncograveyard.com/Dana-44 ... fgodGSsAHA

I run 4.10's and 33's and its a good combo. Does decent on the highway and good wheelin. Would like over drive but that wont happen for a while.

Jantz Jana K4:

http://www.jantz4x4.com/jantz.php?p=detail&pro=jana_k4

or the Nitro Gear big pinion conversion kit, I haven't found a direct link, more than one place selling it though.

4.10s are a good combo with the 33s & the 3 speed or NP.

The "thick" gear set would let you install a 4.10 gear with the carrier you already have.

The Jantz K4 & Nitro kit are nice upgrades to stronger ring & pinions, if you think you'll need the extra strength.