Fast?! What are you being funny?

I'm not fast, I got these 3rd week of July, spent a week degreasing all metal parts & painting so paint could cure fully while I do my harvest... threw my back out the next week & couldn't do much anything for 8days, leaned on my neighbor to load out 5B's for me & do some desicating on peas, got through harvest ok by myself, but my lower back issues have bugged me all winter, couple hrs in the shop a day hunched over working on projects is all I can handle... turning 50 this yr, feel like 80 most days.
Anyways, just about done with this adt & pup
I made a valve divider block from brass for the pup
This dump cyl was on the trk, right side... the flexible hose going to the "T" I think I made it a bit too short, box going up/down - changing angles tugging a bit on this fitting broke it loose from the tube. Pipe goes up to top of tube & broke loose from that soldered joint... buffed the paint off, resolder, repaint, put it on pup after dinner today.
Got the box on the pup, put oil to the cyls
This is where the connection is for the pup hyds
Got a leak, hoping I just over tightened the fitting & crushed the seal too much... put on a new fitting with some thread seal... give a couple hrs to set & try it again.
Made up some exhaust pipes from 5/16 Plastruct tube for this adt & the others
This air cleaner is 3D printed, used an 8mm magnet to hold it place for pictures & filming, leave it off during regular use so it don't get so dirty.
And I'm motivated to get busy putting this WA500 wheel loader together next, it's only 4yrs next month that I've had it

...been using it for spare parts on occasion for other models that needed repairs, still missing a couple parts that'll hopefully show up next month.
Degrease the cyls today & paint them yellow
The drive belt on my lathe is toast

...having a hard time trying to find one locally.
I was looking on
https://www.mcmaster.com/#drive-belts/=1booul2 (I see the link won't go directly to page I was looking at; it's the T5 series timing belt) My operators manual gave the dimensions 124 x 1.5 x 15 which is metric for teeth - depth - width When I measure the length I get 584mm & pitch is 5mm
Gonna be one of these 3 belts

... would the difference in lengths compared to # of teeth be b/c of belt thickness?
T5-575-16 575 115 5 Urethane Gray -13° to 176° 1679K518 9.10
T5-610-16 610 122 5 Urethane Gray -13° to 176° 1679K545 9.51
T5-630-16 630 126 5 Urethane Gray -13° to 176° 1679K522 9.51