Secondary attached rotating Sprite Clipping not pinned in correct position

SDK Get Help
1

macOS
1.12.3

Trying to have ships thrust appear behind ship but cant for the life of me work out the math to stop it doing weirdness and then clipping aka being hidden by its own sprite on rotation.
Both are polygons I draw in code and then manipulate as per below. When pressing / holding UP the thrust sprite appears

clipping

Ship and Thrust code ATM below

function playerShip:update()
    -- draw the ship polygon to the sprite's image
    local img = gfx.image.new(32, 32)
    gfx.pushContext(img)
    gfx.setColor(gfx.kColorWhite)
    gfx.fillPolygon(playerShip.polygon)
    gfx.setColor(gfx.kColorBlack)
    gfx.drawPolygon(playerShip.polygon)

    
    gfx.popContext()
    playerShip:setImage(img)

    -- rotate the transform
    playerShip.ship_transform:rotate(playdate.getCrankChange(), 16, 16)
    -- playerShip:setRotation(playdate.getCrankChange(), 16, 16)

    -- apply the transform to the ship polygon
    playerShip.ship_transform:transformPolygon(playerShip.polygon)
  
    -- reset the transform so that crank change doesn’t accumulate over time
    playerShip.ship_transform:reset()
    local spX, spY = playerShip:getPosition()
    local angle = playdate.getCrankPosition()
    decelerateShip()
    shipDx = thrustSpeed * math.sin(math.rad(angle))
    shipDy = thrustSpeed *-1 * math.cos(math.rad(angle)) +gravity
    local shipMoveDx = shipDx
    local shipMoveDy = shipDy
  
    if (spX < xOffsetmin and shipDx <= 0) then
        shipMoveDx = 0
    end
    
    if (spX > xOffsetmax and shipDx >= 0) then
        shipMoveDx = 0
    end

    if (spY < yOffsetmin and shipDy <= 0) then
        shipMoveDy = 0
    end

    if (spY > yOffsetmax and shipDy >= 0) then
        shipMoveDy = 0
    end

    newShipX = shipMoveDx +spX
    newShipY = shipMoveDy +spY
    playerShip:moveWithCollisions(shipMoveDx +spX, shipMoveDy +spY)
  
end

function thrustShip:update()

    local img = gfx.image.new(32, 32)
    gfx.pushContext(img)
    gfx.setColor(gfx.kColorWhite)
    gfx.fillPolygon(thrustShip.polygon)
    gfx.setColor(gfx.kColorBlack)
    gfx.drawPolygon(thrustShip.polygon)
    gfx.popContext()
    thrustShip:setImage(img)
    -- thrustShip:moveTo(spX+8,spY+36)
    local angle = playdate.getCrankPosition()
    thrustShip:moveTo(newShipX + (32 * math.sin(math.rad(angle))),newShipY+36)    thrustShip:setZIndex(60)
    
    thrustShip.thrust_transform:rotate(playdate.getCrankChange(), 16,-16)
    thrustShip.thrust_transform:transformPolygon(thrustShip.polygon)
    thrustShip.thrust_transform:reset()
end