Here is a complete alignment kit, for less than a any alignment, I know about.
First the toe in gauge. It's made of 3/4 sq tubing, 6.5 to 7ft long, plus 2 pieces 16" long and one piece of 1" sq tube, 2" long, to side over the 3/4 tube. Weld a 5/16 nut to it, drill it thur and tap. I welded a little piece of 1/4" round, on the bolt head to make a small T-handle. Note that there is a projection welded, on both sides of the tools upright.
Adjust it to about .5 - 1" wider than the sidewall of the tires. You put projection on the bulge of the sidewall, at approx the center ht. Have someone hold it there or block it up, to that point. Go to the other side and use a scale, to measure to the same point. Note that measurement. Side the tool to the other side of the tire and measure that distance. The difference will be your toe in (or out). On the side wall, I use 1/16, rather than 1/8.
Camber is the easiest to measure. Again, you use the side wall of the tire. You can use just a straight edge or, I use a 24" carpenters square. It's easier for me to see the degree reading, when it's horizontal. The angle finder is magnetic so, it will work, either way. That will give you a accurate camber reading to as close as you can make out the scales divisions.
Next is caster. To get caster, you turn the wheel 20 degrees, in each direction and take a camber reading. You add those two readings together and that is the caster angle.
I first did caster by setting the wheels straight ahead, then marking 20 deg off the sidewall, with a adjustable angle tool like is pictured and chalk marked the angle, on the floor. I then turned the tire, parallel to the mark and took the camber reading, same on the other side. Caster is the least important reading. Caster can be off 1/2 deg and you'll never notice but, if you do your measurements, carefully this way, it will be very accurate.
For about $180 (cheaper used. I got my set for $50, many years ago) you can get a set of turn plates and it will make caster readings easier.
https://www.ebay.com/itm/164159822197?epid=8043760102&hash=item2638b01975:g:C2EAAOSwRTJelI7cEdit:
Be sure that the surface you use, is actually level and if you use turn plates, that the rear tires are raised to the same height as the plates.
Edit 2:
If you've jacket the car up, after letting it down, you need to roll it, back and forth to settle the supension, back into position.