ah yes if you dont have them you are suppose to. But in all honestly mine broke on the first jump and i made my own tray like mechanism to hold the battery. I think you should jsut fab your own that will hold up better.
I didnt get the delrin stops either man...
I'm thinking of using those 2 spare mounts i have left over - one on the TVP and one on the chassis 'deck' - and will screw a square piece of acrylic to them both =)
you know i am thinking those are not spares then. They may have done away with the delrin mounts and put these in place which would be much better IMO. Wont break off then. I would use them as the stops if i were in your position.