... you know, the little rubber bits around the push rods.
do they mind being greased up?

they're a bit a tight fit in the little holes (this is sounding a bit wrong ) they go in, so the rubber keeps bunching up as i try and push them in. if i was to put normal grease on them to help them on their way, will this destroy the rubber?

You could try a spot of dot4 brake fluid or silicone brake grease.

not sure about brake fluid on my lovely painted chassis
silicone brake grease will be a good call though. as long as its safe on rubber then?

WD40 perhaps? or copper grease? normal lithium (?) grease? just wondering on them since i've got them in the garage already.