@mjs513 - Yep I was/am using normal size headers and even then I am not sure it gets down completely flush...
Also with those SMD connectors, on a different board, I soldered one on and it was real easy to solder bridge over to those caps... Lost one of those caps... T4 sitting on shelf, not sure if it will work or not.
So when I did the next one, I actually used cutter and shortened the smt legs, some, such that the legs did not fully extend out to the end of the pads, which made it easier to solder.
This time I did not do that. But I tried to be real careful in alignment. I used some extra long breakout pins, that I put into breadboard. Did not solder them in. Then placed T4 upside down on them, then used some female headers going sideways to the pins of the SMT connector over to the regular pins on T4, to get it close to being in place. I then used lots of flux, put a little solder on iron. With one hand pushing down on headers holding down SMT connector, until I think everything was aligned, I then touched down the iron on a pin, to have solder tack it down. Did to other one on far end, and then soldered the rest down...
And again before applying power to Teensy, I washed it in hot water, with toothbrush, placed in oven... Until dry. Note using Water soluble flux (2331)...