1) Yes, but 33 springs are shorter than sud ones at the rear. Sud rear axle has a hole that spring sits in, on 33 rear axle the spring sits on top. If you are using sud rear axle, then might be best to go with sud springs..
2)Koni are most peoples choice, spax are good too. Avo do them as well for reasonable money. 33 rear shocks are shorter than sud ones (see above), so reckon 33 shocks if you are lowering the car. Avo will make custom lengths if you ask nicely, and pay a small premium
3) Sud pans are deeper, and will lower the front about an inch compared to 33 pans (BigAl might have a more accurate answer). Think you can only use them in conjunction with early 33 struts with metal strut pan bearings tho - not the later type with yellow-plastic pan bearings.
4) If you are using 33 struts, you will certainly need 33 hub carriers! sud and 33 struts have different mounting lugs at hub end. if you are changing components to get outboard brakes, the drive shafts and hubs must be changed. The rest can stay the same, i think, but most guys who do the swap tend to put a 33 front setup in complete.. 33 beam and arms are different, but is hard to tell how with naked eye.. subtle differences in position of bushes.
Poly bushes are the same for most of the components, only ARB bushes are different between the two.. as far as i know