Can someone please recommend a good, as clear as you can get w/o going nylon, thread to quilt with? This is why I hate to "quilt" because I don't want to mess up the quilt top. I have done a t-shirt quilt and I have a red square in it, also a lot of white in another and am just afraid I'll mess it all up. I really don't want the attention to be drawn to the quilting but instead to the actual squares. Most of the quilt (majority) is black, but if I use black, it will grossly show up in the red square. TIA!! I really can't afford a LAQ at this time.

When you quilt with nylon/transparent threads, you need to remember that the ends can get a bit stiff/pokey. I have the same ideas as you, don't want my quilting to stand out, so I use the closest thread color I can and change the top thread as I needed. There is no rule that says all of your thread has to be the same color.

sulky has a polyester invisible thread it's VERY fine and not pokey at all
you can use something like BOTTOM LINE it's 60 wt polyester thread usually used for the bobbin, it would be fine for what you want and if you use a med grey or taupe, i feel you would have to look closly to see it.

lingerie thread - finer than just monofiliment thread...

just my opinion

Personally, I'd do black thread and then red in the red areas. I hate the look and feel of monofilament.

This is also what I would suggest. The gray color will blend in with all the colors you are using.

This is a great idea!

Also, I've gotten used to having same weight and brand of thread, but different color in the bobbin to suit the back versus the front.