There is a slot on one (or maybe both) Of the black mounting brackets on the meter. You can mount it to your engine here. You may have to take an old prop and cut the blades off and use it as a washer to fill out the space so you can tension the prop nut. The thrust is most likely not causing your trim issue. I am surprised your readings are zero on both stab and wing.
Make sure the elevater is in its nuetral position and measure the wing at the root. clamp a stick to the elevater to make sure it stays put.
Any trim you carry is no biggie really. Usually people are just embarrassed about how it looks in the pit area.