You can screw little bits of wood into the sidewall near the rope too so that it elevates the front edge a bit so if you drag this on the road it won't wear out the rope so fast.
Also for weights, I discovered if you slash the sidewall just a little on each side (i used a jigsaw, but a hack saw works too), you can fit a 45 in there and pile more weights on top of that too. Rocks work too of course, but tough to measure the weight of rocks if you're tracking the weight you use.
I'm discovering there are always simple solutions to pretty much any problem.
I am Anton Zdravko Martin!
Best meet lifts: Sq 150 Kg (330 lb), Bench 120 Kg (264), DL 160 (352) @89 Kg (197)
Best gym lifts: Sq 375, Bench 280 (pause), DL 385 @205 or less
Goals: 3/4/5 while healthy and fit
"Hack away at anything which isn't essential. Do what you love, and do it often." Fazc.
"Everything competes for recovery so more assistance is not always the best idea." miked96
"Squat:15 sets of 3 with 150Kg
Deadlift:15 sets of 3 with 150Kg
It's not rocket science." Big Swede