Sylvain....it does not look like it is much out, I would weld up the hole, grind it back and re drill to suit or you could make the hole oval and then weld up one edge of the hole and file to fit

Could you warm up the tube where the upright and cross member meet and tweek it out wards with a bottle jack and a length of pipe, dont forget you only need to move each side half of the amount that its out if that makes sense

Arfon

Hello guys,
Thank you very much for the answers.
Arf, unfortunately, I don't have anything to heat-up the tubes, like a blowtorch (I just have my lighter, but I don't think it will be sufficient:) ) But thank you, it could have been an easy way to get rid of the problem.
I chose the option to enlarge the holes. Now they are oval, but at least the roll-bar fits. Actually, it doesn't move even move left and right, as the bolts are holding it on the "new" outside edges of the holes, on each side. I'm tempted to keep it like that, but I will try to weld up the edges and grind to go back to round holes as Kev adviced.
Thank you very much for the help.

That's what I ended up doing to my bar as it shrank.
Bit of a bodge but I'm happy with it still.

Hi,
I'm digging up this "old" thread just to update it. And because I'm very happy today.
First I want to thank you guys for your help, with special thanks to Kev' for his good advices (as always). Today, I could "repair" the fitting holes of my roll bar. As I said above, I enlarged them, and they were oval. Today, I finally decided to add some weld on the inner edges and grind them to recover nice and round holes. I delayed it because I was not sure if "I could do it". But it actually worked very well, and now, my roll bar fits perfectly!
So Thanks again to you guys for the help.
Here are a few pictures:

After I enlarged the holes two weeks ago.
Attachment 1557

Today I added weld on the inner edges. Grind flush, grind "round" (sorry, I can't find the English word for that)
Attachment 1558

All the holes are OK now and and the roll-bar fits !
Attachment 1559

Glad I could help mate.....now get some paint on it:D :D