Want to find a high quality tint that isn't dark but is good at keeping the interior cool. Anyone have good first hand knowledge and can suggest a quality product? I want the lightest tint possible but still get good heat rejection. TIA!

I believe 3M has the state of the art. Now I'm where it gets 122 F , and I solved that question
AT THE TIME , technology improves all the time , by simply getting "samples" from all the places with different tint brands they claim is best for "heat rejection" ; then you put each one by one up to your glass with your hand being the judge on a really bright sunny day - and before the ambient temp rises to confuse your hand. You want to see how the infrared / UV? whatever penetrates your glass & then tint film to your interior.
I was surprised how some bragg bigtime films really actually SUCKED

I had fantastic experience with Llumar Formula One Pinnacle in my 370Z, but for some reason, whatever the heck is in my Titan is the best I have ever had. I believe there's a tag for it somewhere in the glove box - the dealer had it done before I bought the truck. I've been very impressed with it.

You want to buy a nano ceramic tint and get the front windshield tint

Live in Costa Rica now and bought a mint cond. 350z but the only flaw is the ageing rear window tint is blistering. This window is equipped with the defogger deicer strips placed on the surface of the glass not inside of the glass. I am very concerned about removing the old tint for I am sure it will involve a scraping off of the tint with a razor blade, something I just don't want one of these shops here to attempt, any one done this before without damage to heat strip elements?

To back up macgiver on his advice is yes the 3m SOLAR Block tint worked on my Cummins turbo truck years back. The puney a/c compressor was so weak I took the truck right back for a refund of my money (did not go to well to say the least) was referred to a shop that guaranteed the 3M film to block out the heat and the film was actually kinds of light in tint not at all super dark. AC worked perfectly after the tint job! 3M does not make any weak or bad products but that is just my opinion.