Rtab Grease question

Hi guys im wondering if theres any spray lube for the polyurethane bushings that wont wash away after some rain. I sprayed a whole can of silocone grease and it squeaked when it rained, than i sprayed a can of lithium grease and it squeaked again when it rained today. So my question is



1. is there a way to grease the poly rtabs without taking out the bushings?

2. is there a way to not mess up the alignment after taking the bushings out?