Unanswered E3D V6 Installation

Hello All,
This is my first post as I am new to the forum. I have the R1 Plus and am looking to install the E3D V6 upgrade. I have the hot end all assembled but I noticed that the Heat Sink does not fit into the shroud when replacing it from the old heat sink. Is there any way around this or is it possible that I have an incompatible hot end model?? Any help or direction would be greatly appreciated!
Original Hot End/Heat Sink
New Heat Sink
Thanks!

 

Yes I have already printed a new quick release and fan holder, could you link the fan shroud again as I’m having trouble locating it.
Thanks!

 

Okay! I have everything installed but I cannot seem to find a link for the firmware that is still good and a few google searches turned up nothing.

 

The guide said that the firmware needs to be modified for the new thermistors.

 

#include "Marlin.h"
#include "SdFatConfig.h"
#include "SdVolume.h"
//------------------------------------------------------------------------------
/**
* \struct fpos_t
* \brief internal type for istream
* do not use in user apps
*/
struct fpos_t {
/** stream position */
uint32_t position;
/** cluster for position */
uint32_t cluster;
fpos_t() : position(0), cluster(0) {}
};
// use the gnu style oflag in open()



Why is the "struct fpos_t" doing an error if I'm not modifying it... could it be bugged to begin with?

*copied error message*
Arduino: 1.8.5 (Windows 10), Board: "Arduino/Genuino Mega or Mega 2560, ATmega2560 (Mega 2560)"
In file included from sketch\SdFile.h:27:0,
from sketch\cardreader.h:8,
from sketch\Marlin_main.cpp:44:
SdBaseFile.h:38: error: using typedef-name 'fpos_t' after 'struct'
struct fpos_t {
^
In file included from sketch\Marlin.h:10:0,
from sketch\Marlin_main.cpp:30:
c:\program files (x86)\arduino\hardware\tools\avr\avr\include\stdio.h:950:33: note: 'fpos_t' has a previous declaration here
__extension__ typedef long long fpos_t;
^
exit status 1
using typedef-name 'fpos_t' after 'struct'
This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.