MPU-6500 FIFO bytes come out in wrong order

When I read 6 bytes of accelerometer data in a burst starting from address X_OUT_H the bytes come in the right order. However when I read 6 bytes in a burst starting from FIFO_R_W the bytes are completely mixed up. What is wrong?

      spi_read_reg(0x74,6)                  // read 6 bytes from fifo

local x = data[0]<<8|data[1]          // left shift high byte and OR with low bye

local y = data[2]<<8|data[3]          // left shift high byte and OR with low bye

local z = data[4]<<8|data[5]          // left shift high byte and OR with low bye

if(x&0x8000){x=-((~x&0x7fff)+1)}      // to convert two's complement to a float

if(y&0x8000){y=-((~y&0x7fff)+1)}      // if the bit15 is set

if(z&0x8000){z=-((~z&0x7fff)+1)}      // invert the bits and add 1

x=x*61e-6       // each digit is 4g/2^16=61ug

y=y*61e-6       // each digit is 4g/2^16=61ug

z=z*61e-6       // each digit is 4g/2^16=61ug

server.log(format("X:%0.6fg, Y: %0.6fg, Z: %0.6fg",x,y,z))

Actually I wan to read 16 XYZ accelerometer samples in a burst, so i want to do a 96 bytes read burst. is that possible?