stackheight is too large (threaded headset)

Couldn't say for sure, but it sounds less terrifying that riding a bike fitted with a headset that has had bits ground off it. A loose headset is pretty easy to notice as you'll get a clunk every time you use the front brake. If you're worried about sudden dramatic failure then go and spend less than £20 on a Tange Levin (which has a 33mm stack height vs. 39ish for Record Strada) and try that before grinding anything off anything else.

I don't have a front brake, so that won't happen.. I'll just try it like this, if the locknut will come off I will notice it and try thinking of a solution..
Untill then I'll just keep it like this.
Thanks for the replies!