A4 B6 hu install going wrong help!

Yes the B6 only has permanent live going to the power connector for the HU, so the only way to easily get the HU working is to pair the perm live and ignition on live and connect them both to the perm live. You then have to remember to turn the HU off manually.
There are 2 ways to wire the ignition on feed.
1. as described in the link above, but then the HU will only work with the engine running or the ignition fully on.
2. tap the thin red wire running underneath the steering column, and feed this to a relay, then power the relay from the perm live at the HU. This will give you a proper accesory feed, so that the HU stays on until the keys are pulled out. It seems to be the only feed in later Audi's that stays live until the keys are pulled out, but isn't man enough to run the HU without a relay. The wire is very very low ampage, so much so that you can't use a piggyback connector on it, you have to cut it, and then reconnect it with a small terminal block.
And yes the fixings on the steering cowl are ****** stupid, I had to modify a long thin screwdriver to get them off, but IIRC you don't have to remove the cowl, just the trim around the steering column, which is just a few 10mm bolts. This will give you access to the ignition wiring running from the left of the steering column.
You'll need the fakra aerial antenna adapter for the aerial, as it needs power for the aerial amp in the boot.
http://www.caraudiodirect.co.uk/fakra-aerial-adaptor-p-5632.html