Keith, forget the polishing compound stuff - it'll take time to reach you, and cost probably three or four times more than the same sort of stuff from other sources. If the clear part's not too bad, you can use toothpaste. I've normally used either 'Brasso' or 'Duraglit' metal polish, but the best so far has been ordinary 'T-Cut' colour restorer, as used on car bodies. Use it sparingly, on a soft cloth, and then wipe away any residue, which, if dried, will be a sort of pale yellow powdery deposit. If still damp, it'll be an off-whitish gunge! Then, just polish with a soft, clean cloth. If you really want to make it look crystal clear, then either brush with, or dip in Johnson's 'Klear' (Future).
To prevent bleeding under the tape for future attempts, once the tape is in place, and pressed down, brush the edges with a clear coat. Again, Johnson's 'Klear' is ideal for this. It'll seal the edges of the tape, preventing any paint from seeping under and spreading anywhere.
Once you've painted the frame work, when it's totally dry, give it a coat of the relevant clear coat. This will help stop any paint rubbing or wearing off during subsequent handling. Seems a lot of work, but it really doesn't take long, and is well worth the extra effort in the end. It also helps to blend-in the framework, to make it look the same shade and 'texture' as the rest of the model.