hiya jason,
I am pasting a message i left on wii chat, myself + girlfriend comblined have sorted the problem!
If you knew me, you'd know i love projects. (not that playing a wii is a project)
Last night my girlfriend helped me crack it..
I centered the image, everything was central.. the wii sensor was in the MIDDLE of the screen/image..
stood back as far as possible.. wallah!!
it was savage, killing 6foot tall zombies!! perfect aim!!
The crack for it is a smaller sensor bar!! as someone mentioned : "if you widen the sensor, in effect your moving closer, if you bring the sensor closer, in effect your further away" ...the only thing that threw me off was the above below set up! the sensor on my 100 odd inch screen had to go in the middle! looked a little silly with props but now i know what i need to do..
as an idea, i was thinking of getting a bike LED, know that ones that come on or flash or do an effect? they are only lets say 10 cm apart.. and modding it to light up IR leds!
maybe bust open a couple of remotes no longer used and take out the IR LEDS ? that'll be the first test.
otherwise my issue is Sorted!
you say you have 80"? i say do something to pop the sensor into the middle of your screen, brush upside down or boxes - doesn't matter, just test it.. 80"...i'd say stand 15' away if possible!
test it ands let me know if you agree it works! don't worry about the sensor being above or below, i was thrown off by this for days! (I only borrowed my mums wii the other day - don't own one)
I'm ment to be the brain in my partnership, the girlfriend sussed the sensor in the middle of the screen!
it was really bugging me

...it worked perfectly on my 41" tv..
now i need to by or mod a closer IR reciever!