Thanks Bobby for including the MATCO response!
As Tony mentioned, a 1/8" pin doesn't want to go in much less thru to secure the axle nut.
Confession: At last inspection I used 2 pins inserted from opposite sides since the Home Depot Aviation aisle didn't have anything to fit.
When I mentioned not having the correct pin down the field at the FBO maintenance hangar and coffee supply shack, Harold the A&P/IA (and D-Day Veteran) turned from his dusty desk in the dusty corner and replied "That's the dumbest excuse I've heard in a while!".
Well...the wheels didn't fall off, but I located and installed the correct pins ASAP.
Lesson Learned!