Try to go reman whenever possible. Manufacturers tend to make a “one size fits all” axle, which really means it will fit every car except ours. If you look at your original shaft and compare it to the new one you will see a raised lip on the outer CV joint that slides into the hub. The clearance inside the knuckle is too tight for that lip to be there, so when you tighten the nut that lip actually presses against the knuckle itself. I’ve also seen axles where the outer CV cone is just too large. You have three options: grind away some of the backside of the knuckle to increase the clearance, buy a reman or reman your originals so that you don’t have that raised lip, or buy new EMPI axles. I think they got bought out by USA Industries, but I’ve been running those in my 87 Coupe for the last 5 years or so. The quality is decent and price point is good. My Coupe has the 108mm axles that you can’t get parts for, so I swapped my transmission flanges for 100mm ones that are a dime a dozen. Wherever possible I would still go reman.