Yeah the TCA bobbles are more profound on some than others, if they're causing a problem, tickle them with a grinder (but remember to re-paint/underseal afterwards).
Once you take the rad bar and bumper iron off a Mk3 the chassis legs are amusingly free- I usually use a small rachet strap to pull the legs in if required, it takes worryingly little force!
Lance- mine flew on too, but it only takes a light tap to a curb (which 50% of these Polos have probably had over their 15+ years) to knock them out slightly.
1 or 2mm is fine, the clearance for our frames is only 0.5mm (M8 bolt) but we'd rather they're tailored to suit each car and fit nice and tight, rather than go on really sloppy and don't do much for chassis ridgidity.
Hope this helps,
Pete