Will front end components off of a 95 del sol SI fit a 88 CRX HF? I'm trying to get this car ready to sell and while replacing the tie rod ends I noticed a upper ball joint loose. The CRX doesn't have p/s the del sol SI did have

 

EG and EF UCA mounting points are different.
Some UCAs are non-serviceable - the stamped steel has a good change of deforming when you press out the old ball joints.
Not sure if the UCAs you are looking allow for the ball joints to be replaced.

If they are THAT far gone, then the bushings are likely worn too.
I would pick up new UCAs from RockAuto. $24.
Comes with new ball joint and new bushings.

Or, just sell the car and take $20 off the price if the customer questions the problem.
It's a 1988 car... of course it's not perfect and needs work.

 

I'm nit trying to throw s wrench into the above reply but I personally without a doubt used sk2 Uca's from a eg on a ef

 

Not sure about the old SK2 kits, but they now carry separate kits for the EF, DA, and EG/DC.
The DA bolts up to a an EF, but changes geometry because the ball joint is in a different location.

Notice that the DA is wider than the EG/DC.
Google search will show quite a few people that have tried DA as well as EG/DC UCAs.