I have an MS in ME, but am no suspension expert. My practical shade-tree experience is that people make absurb claims about unsafe suspensions. If the wheels point straight (toe-in) and are fairly vertical (camber), the car will go down the road fine. You can't adjust the caster much. This assumes the vehicle was well-designed for the tricky things like how wheels track on a turn and if the rear end wants to swing around.
The biggest suspension/steering concern is if things are loose, especially the steering. Seen an old movie where the driver is constantly moving the wheel back and forth while driving down the road? I rode in a van in Indonesia where it looked like the driver was fighting 30 deg of play in the steering wheel, and that was a government vehicle. No wonder they roll off mountain roads when they hit a bump.
Once I adjusted the height of my 69 Dart to factory specs, not much of a change as I recall. I didn't know that drastically increases the toe-in. In less than 100 miles on a camping trip, the new front tires were ruined. The car drove straight though. The counter-point is that as a front end sags, toe-in decreases, so if you don't re-align every 5 or 10 years it will change to toe-out which causes a car to wander.
In another case, our minivan was hit in the front side, which bent the left front wheel inward ~20 deg. GEICO fought paying, so I fixed it myself while suing them. Initially, I could only get the wheel to ~5 deg of vertical (after filing strut slots). People said it would never drive right, but I drove it that way for at least a year. It drove perfectly straight on the highway and the tires didn't wear abnormally. Eventually, I used a ram to bend the upper strut mount and front frame back, and got the wheel caster perfect, plus GEICO paid by then.
In your case, I can't see that a slightly shorter spindle would affect things much. Imagine a line between the center of the upper and lower ball-joint. Think of that as a "vertical axle" ("king-pin" in early cars?). Ideally, where that line hits the road will fall in the middle of the contact patch of the wheel in the inward-outward direction. A shorter spindle hardly changes that. A much bigger change comes from changing to wider wheels or ones with a different offset. The other thing to consider is how that vertical axis is inclined in the forward-backward direction. The more it leans backward (caster), the better. You want it to hit the road in front of the contact patch. That will give you better "shopping cart" effect (make car follow better using a tow bar). Too much, and you must force the steering wheel more to turn. We can never get enough caster since A-bodies were designed for bias tires which flex the contact patch backward more than radials. Look at your spindles and see if swapping them left-right will move the upper ball joint center back more, which is good. You will bottom out sooner on the rubber bumper when the front end lifts, but unless you are taking San Franscisco hills like in the movie Bullet, little concern.
