I just did a T5 ECU the other day and found it so much easier to just tin the pins (keep them in the alignment holder) and put a drop on each pad on the ECU, after scraping off the rubbery protection. Then just join the pins to the pads. I wrestled with getting the pins through the holes on a few T7 ECU's and it just isn't worth it. The above method took about 2 minutes and worked perfectly.