Hi, I'm thinking of making up a down pipe for my S70R straight flange.

After looking at what is needed I have come up with OEM flange cut off and welded to a 90deg mandrel bend (not sure on the diameter) joining to a flexi, then to a 45deg bend and finally join to the original exhaust or continue with a full system..

Does this sound like the right parts needed? My only concern is not knowing the correct diameter as ideally I would want 3" but I know the flat flange cannot accept that.

Of course I will need to weld on an insert for the Lamda.