saturn pad + sf 3rd strike

[STP]

i've been searching for a solution to play 3rd strike with a japanese saturn pad.
but every converter i've tested jet sets a,b,x,y,l,r instead of a,b,c,x,y,z.
but i hate to play beat em ups using the l+r trigger buttons.


now i'd like to mod my pad or build an adapter even if it means to make the pad useless for other games.