"We Filipinos are one of the best in the world when it comes to technical jobs."--> agree with that! Bigyan mo lang ng tip yung gagawa, solb ka na!
If you sense that the sound is the same "trrrg" even after you twisted it, chances are something else causes the sound in that area. Maybe you could be better off with lowering the pipe just slightly, or while it's lowered you could reattach that metal piece under the tank. That way you solved two problems in one go. Kasi kung lower pipe lang, baka bumalik ung tunog and you'll have to do it again.
I would suggest against twisting it even more, baka masira pa yan. If you have time you could lower the exhaust pipe a bit, remove that metal piece if you can, and restraighten and install some form of cushion like rubber pieces, bushings, or anything that will prevent the sound. Maybe before that there was something in between that got disloged so I'd look for signs. If you can't remove it, see if you can stick something in between.
I don't know much about clutches, but if it's slipping then I'd have it changed sooner than later. Mahirap na, alam mo naman ang MMDA madugo at hindi bibigay unless bayaran mo. If you'll have it changed, upgrade ka na rin ng konti to a better one. Ask around while you can. When my dad's clutch will go he mentioned to upgrade it to a better one. But if sources tell you that it's not going to be a good bargain, I'd stick to OEM.
The mechanic I know is in QC, go up north sa Commonwealth until the Fairview area. Yung Caltex dun suki kami. It is beside a McDonald's resto. Park inside Caltex and look for Efren, Tino, Jun, or Felix. They've helped us since we had a 1989 Lancer, so that's roughly 16 years ago. Tell them yung anak ni Dr. Garcia referred you.
I came here as an immigrant, nothing special really. I'm getting homesick by the day. I use my technical knowhow to DIY my own car. Labor costs here are much higher than ones there kaya the US benefits by paying foreign countries low wages for the same job.
Once I owned an old 1989 Lancer and it always overheated. Back then I never knew anything about cars. I don't remember changing the oil on that poor little thing.

It's A/C always bogged down especially in Manila traffic. Somebody eventually bought it last year. But when things got bad we just sent it to them sa Caltex and they took care of it--changed radiator, fixed lights, A/C leak, clutch system (it was also slipping), and changed rear shocks.
Btw, do you have online images of your car?