I got frustrated with killing savox servos, so i thought why not use a spare MG996R servo i had spare from the erec. I had to completely redesign the selector to fit everything. I have tried it using a pair of 6x10mm springs with 0.8 wall thickness and it works very well. id recommend starting with 0.5 or 0.6 springs to start and work up if needed. The hole tolerances are quit tight u may need to adjust to suit your printer. please check the cad model for bom