In my very recent experience, i got to ride up front in a big twin prop. on RPT. mind you i did no both the crew (good mates off mine) and got invited up there.
maybe find out were the crew hang out mate, drink lotsa beer with them form time to time and than ask?
good luck.
i really enjoyed it and was nice to see what they do (my mates) during flight. (not to much it seems but drink coffee while the autopliot fly's lol)
yea yea yea i know bad wx and all it becomes hard work etc etc....
cheers
