I have used solartex quite a bit, including right now on a BUSA DH-4. I have not had good results using it for trim. What I find is that the trim will shrink when heat is applied and I get wavy lines. I suspect you will see it wrinkle up when you tack the trim to the base color and you will have to get the iron close to the seam when you install it. I agree with Tom that it would be best to paint the trim. I have used epoxy, rustoleum, polyurethane, nitrate dope and latex successfully on ST. Also agree with Gray Beard on the opacity of ST.
Chuck