That's how all the ones on my UPS look, I just tinned the wire and made it a U shape making sure the insulated part of the wire was on the left hand side.
Never do that! Never tin stranded wire that will be clamped in a plug or terminal block. The reason why is that solder will plastically deform at a low level of stress (i.e. it will move and not spring back). As the temperature of the contact changes, the tinned wire is alternately squeezed, as the temperature drops, and relaxed as it increases. Each time the solder deforms a tiny bit more and eventually the contact goes high resistance or maybe even open circuit. With mains wiring, this can be a fire risk.
I had personal experience with this some years ago, I had an intruder alarm, which was prone to false alarms in the anti-tamper circuit. I couldn't find anything, and eventually resorted to keeping a diary of the events. After a few years, it was clear that the false alarms were most common in March and September. What? Well the diurnal temperature change generally reaches a maximum in spring & autumn (days are still warm but the nights are getting longer & chillier) and the alarm box was exposed to these temperature changes. A few minutes up the ladder revealed the wiring from the anti-tamper microswitch to the alarm box PWA had been - tinned and clamped in terminal block! I soon fixed that one, and no problems since.