If I had to, I would use some impact tape and try to get a rough estimate of the lie angles for you. Then I would draw straight vertical line on the ball and use impact tape to fine tune the lie angles. You have to account for shaft droop, unless you spine and flow the shafts, which is pricey. So, let's say you feel best playing at 1* upright. I'd get the clubs bent 1* upright and then use the line test and your 4-iron may need to be 2* upright, your 5-iron may need to be standard, your 6-iron may need to be kept at 1* upright, etc.
That being said, IMO a lot of this depends on what you are trying to do with your golf swing. If you're trying to flatten out your downswing and go from a downswing plane on the TSP to a downswing plane on the elbow plane, you need to change your lie angles because if they are kept upright, you'll just keep coming down on the more upright TSP.
I agree with lie boards. They're garbage.
3JACK