I almost cut one for the bucket truck last week, had to back into a steep driveway to chip brush, half a box of chips and an 8000 pound chipper behind it on a 15 degree hill, parking brake would not hold the truck, second time this year ive had this issue, bunch of chocks worked thoBrake pedal depressor-log.
edit, forgot to mention, this log works on any sort of brakes, but hydraulic brakes can bleed down, and as the log isnt going to account for that it can certainly be an issue, air brakes will keep dumping air into the brake chambers should there be a leak in the system anywhere
wreckers have a "winching brake" which puts down any lift axles, and applies all the service brakes
I was thinking throwling to keep it compact, but I can see how it may be too strong and/or impossible to remove with gloves onGo for cheap hardware store cord, thicker and weaker.