switch(FEAT_ROADVEHS, SELF, switch_pickup0, [
    STORE_TEMP(CB_FLAG_MORE_SPRITES | PALETTE_USE_DEFAULT, 0x100)
]) {
    default: spriteset_truck;
}

switch(FEAT_ROADVEHS, SELF, switch_pickup1, [
    STORE_TEMP(PALETTE_CC_BROWN, 0x100)
]) {
    default: spritegroup_box;
}

switch(FEAT_ROADVEHS, SELF, switch_pickup, [
     getbits(extra_callback_info1, 8, 8)     
]) {
     0:  switch_pickup0;
     1:  switch_pickup1;     
}