Lower Ball Joints 67 v's 71 C10

[chevy one]

I found a deal at the bone yard. A 71, 2WD C10 that had upper ball joints, tie rods, rotors, calipers, backing plates, bearings/seals & sway bar with new poly mounts. When I say new, I mean new, never drove down the lane, unless whoever was a complete idiot. Looks like someone started a project and gave up. The new tie rod turn shackles never had bolts installed. All for $60 + tax of course! Spindles are OEM stock height. I only robbed the upper joints. I will be buying quality MOOG lower joints being they hold most of the weight.
When converting from drum to disk using the stock 67 A-arms can I order and install new ball joints for a 71 C10 disk brake setup or do I need to order the ball joints for the 67 arms? Should I have robbed the A-Arms as well? I installed new bushing already in mine last year.
When looking at Rock-Auto they list different part numbers from the 67 to 71. I am assuming this is because of the drum to disk spindle change. Any light that anyone can shed on this would be great.
Thanks

[gringoloco]

The lower arms are the same. You will need the Ball joint to match the spindles. Good score!

[68c-10]

I did this exact swap and I used my stock A arms with new 71 ball joints. I also used the stock 71 spindle, rotor, and caliper. The only thing I had to due to me not having the tie rod ends or the money, was to put the spindle in a mill and mill down the tie rod pad to match the 68 thickness, The taper is the same. Sense you have the 71 tie rod ends and sleeves you should not have this problem. Another small thing is the 71 has the brake line and hose on the front of the crossmember and the 67-68 at least has the brake hose and line on the back of the crossmember. I used shorter brake hoses from a caprice.

[chevy one]

Thanks for the Info; I thought I was on the right track. I am thinking of going back for the brake lines. I did notice that they were routed different. One more question; I will need a brake booster valve. The OEM stock is a little costly around $145. I can get an Adj booster for around $75. Dose anyone know a site for a better price of the OEM style?
Thanks again!
Chevy One

[68c-10]

I used a stock valve from a newer (80's) truck that is made out of brass instead of the cast iron one from the 71. I just got it from a salvage yard. I also ordered a master for a 71 and it bolted right up.