[Solved] [1.7.10] Blocks bordering custom TileEntity not rendering correctly

I'm running into a rendering problem. I'm using a TileEntitySpecialRenderer to render my model, which is working as expected. However, when my block is placed bordering certain blocks, such as a lit furnace or end portal, the corresponding side on that block will not render correctly. It appears as if I haven't overridden IsOpaqueCube(), but I have. I've provided a screenshot and some relevant code, and can provide more if needed. Thanks.

Edit: If I change the light level of the block to zero, it works. having a light level leads to a different call in BlockRenderer.

Edit 2: I messed up and setLightLevel(10.0F) when it should be less than 1. replacing with setLightLevel(0.5F) fixed the problem.

    @Override
    public boolean shouldSideBeRendered(IBlockAccess p_149646_1_, int p_149646_2_, int p_149646_3_, int p_149646_4_, int p_149646_5_)
    {
        return true;
    }

    @Override
    public boolean isOpaqueCube()
    {
        return false;
    }

    @Override
    public int getRenderType()
    {
        return -1;
    }

    @Override
    public boolean renderAsNormalBlock()
    {
        return false;
    }