Can I use this Music Wire torsion spring: http://www.amazonsupply.com/dp/B005XQEEEO
This part has about the same force as the mcmaster music wire spring, but slightly larger dimensions. Will it still fit?
I also found that amazon sells 4-40 threaded inserts http://www.amazonsupply.com/dp/B00270ZSIU
They don't have the 7/16 SHCS so here's 1/2 http://www.amazonsupply.com/dp/B00EDUU6YS