poly bushings for sure, no point in upgrading sway bar unless it pops, especially on a van thats probably not built for cutting corners. and spend the extra 20 a corner and buy new strut mounts for your GP. You'll regret it later if you don't and in 10k your pulling the rears out to put new mounts in. Well worth it while your replacing struts and springs. For your GP check out Summitracing.com for a sway bar if that one does go. They have the GM Performance Parts bar for 65, which is MUCH cheaper then jap OE replacements!
