Problem changing Distributor belts

[03ClioSport]

My 03 Clio sport is up for maintenance and it's time to change the belts, pulleys, etc. I've already changed the distributor belt without any hassle, however, the accessories belt (alternator, P/S, etc) is another story. I cannot seem to get it in. I've dismantled the projector, bumper, eveyrhting you can think of and I can't get the belt in. It has this spring which is IMPOSSIBLE to put pressure on so the belt can be loosened enough to get around all the pulleys.

I would greatly appreciate any expert's advice.

 

[GR172]

The engine mount needs to be removed and by pivoting the tensioner the spring will be compressed. The tool in the picture is "Mot. 1368" from Renault but as far as I can see it's just a half inch (12.7mm) square drive.

Hopefully someone else can advise whether any old normal ratchet would do the job.