Hey Danialan
Great work there - been through a lot of this in making bumblebee (see below) which is a 109 cut tub and had to do a lot of similar bending - I did all mine without heat no splits - using wood clamped work well as get nice right radius corners on bends
Re Rivets
For anyone reading this post buying an air rivet gun will be one of your best investments if you undertake such a project - there are lots of rivets to remove then replace (buy a 3 packet of same sized drill bits for drilling out and new holes too)
Paint removal
You seemed to have sanded - I gave up in the end on sanding and opted for much easier paint stripper especially if the alloy has had a few paint jobs - lucky yours was original paint but more layers means more work and paint stripper so much easier esp for difficult spots (vs flat surfaces).
Rivet finish
I used a very small brush and applied some etch primer (sprayed from a can into a glass jar then applied using tiny brush) to the rivet heads. Then did the same with the top coat paint. Rivets come up pretty good.
We used a 2 part mix paint - followed the mix proportions and virtually no runs - pretty good for a 4x4 home job. For anyone considering doing their own painting find a helpful (note comment in earlier post) paint shop with plenty of qu and advice will get the job done.
In the pic below of our Stage 1/Defender/shortened 109 tub/rangie chassis/extended cab you can hardly see the painted rivets - did the same for the black capping (2 pac painted galvanised capping) where all rivet tops hand painted black or yellow as appropriate
https://www.aulro.com/afvb/images/im...013/11/426.jpg
https://www.aulro.com/afvb/images/im...013/11/427.jpg
Keep up the good work.
Skiboy

