Thanks all, I knew you all could make some sense of this frame.

So this one is like some other 400s out there. The SN starts with 405 which indicates an 89' year but painted in the 88 colours.

I thought the sport tour set up had brazen ons for racks as I have seen them on other 400s.

I looked at the Vintage Trek site but can not get the cat to show up. My computer sends it to a viewing site that I can't open. Have not been able to by-pass it.

Good to know that Trek mixed up their groups. I intend on doing this frame with either Shimano 105 or Exage 300 parts.

Thanks for the insight and kind responses.