Im wanting to go up to stage 2 now , 180+ bhp hopefully#

my engine is bog standard apart from a full exhauest system but there are a couple questions i need answering please

can i keep the standard T2 ?
what actuator do i need -31 or -34 whats the difference?
do i need beiges ?

anything else u guys can think of would be a big help

motorsport developsments can offer a stage 2 @ £525 but ive seen beiges on ebay for £109


Ben