You do need to run the plastics, as neo71665 mentioned, but as for the angle of the carb ideally you would get an angled clocking flange and riser. ComposiMo fabrication makes a really nice one at this link,
http://www.composimo.com/GY6-Angled-...ange_p_11.html but depending on how much height you need this is another option from the ruck shop:
https://theruckshop.com/product/trs-...lange-56mm-v2/ .