MUSE opto-mechanical design and performance by Hénault, F, Bacon, R, Dekker, H, Delabre, B, Djidel, S, Dubois, J, Hubin, N, Lantz, B, Lau, W, Le Louarn, M, Lewis, I, Lizon, J, Lynn, J, Pasquini, L, Reiss, R, Roth, M