Well the dampers aren't any kind of strut. A strut is a damper that sees side loads and located the suspension, the shocks on the supra do not do that. Macpherson struts, chapman struts, etc, are not on a supra. Strut started being used by people that didn't know what they're talking about and I would like to try and help stop that along with the use of dampening, but I guess this is not really the time for me to complain about poor vocabulary when talking about suspension. So ignore it I guess.
Well he could climb under the car and check the condition of everything. Try and move stuff around see if anything has excessive play and should be replaced. I mean that would be the way to do it. But you're also dealing with 20 year old bushings which are not meant to have that long of a life.
And your engine analogy was flawed. A slight miss does not equal, oh, you took out that part.
Just get under the car and check out the suspension or take it to someone and have them check it out. If you've been dealing with this for a month and haven't even gotten under there to look at it, then you aren't going to fix it by posting on the internet. A clunk could be a lot of things, there are some good ideas in this thread, but you won't know until you check it out. Or buy all new bushings and new shocks and take it to someone and have them install everything and then it should be gone and your suspension should feel good.
But there's a lot of old, crappy rubber back there, that needs attention.