Control arm length and lift height?

I have a set of Rusty's LCA's that are about 16.25" eye-to-eye. I like them because they are clearanced inward to allow me to run stock wheels and my 31's. I have OME springs that started as 3" springs, but the P.O. said they're probably good for 2.5".
I don't want to lift more than I have to. My fenders are plenty open for the tires as of now.
Can I lift only 2.5" and still use the arms? Should I just get some .75 spacers and be done with it?

Yuccaman's chart says stock is 15.75, 2" and 3" is 16", and 4" is 16.33". That should put my LCA's best lift height somewhere around 3.5".

Is there much of a difference between 2.5 and 3.25"? Seems like a trivial amount, but I don't want it to sit too high.

Any help is much appreciated...

It should be fine. Worst case scenario, it moves your axle forward .25"-.5", which isn't going to cause you any problems.

This is assuming appropriate UCA length to keep caster and pinion angle in spec..

I'm confused. Isn't he talking about adding more lift? Would that not move the axle backwards?

Sorry,
Right now it's on saggy stock springs. I'd rather not mess with the UCA's yet. I guess the question is: how picky is the pinion angle? Can I run LCA's that are a quarter inch too long (if at 2.5" lift), or should I shoot 3.25".

I think I'll just pick up some .75" spacers to give the 3.25" lift and stop worrying about it.

Pinion angle and caster are quite important. If you install the LCAs and the caster/pinion angle are off then you're certainly going to need to mess with the UCAs. Put the new LCAs and the springs on. Check your caster angle and if it was close to the same as before then let it ride. If you get much more than 3 inches of lift you need to go with drop brackets or long arms. But I guess you know that if you've been reading yuccaman's site...