Here's a photo of the internal brake mechanism on the 102:
The "push rod" and "pivot ball" are what I assume is missing? That was a highly dangerous choice made by the PO. No brakes is a bad idea, would be even worse for someone like me because of the constant high-speed operation on roadways my Cubs see.
I do have my parts 105 laying around, brake should be the same other than the absence of a clutch. I can dismantle the brake and get dimensions, then get back to ya.
I need to remove the hydro from the parts machine anyway to steal some stuff from it for my 147, so it's no biggie at all.
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'70 107 with k301 engine swap
'71 106 with 38" deck
'70 147
R with factory replacement k321, 42" deck
'61 Original with 38" timed deck
'63 70 "pinkie"
1863 with 54" deck
'46 Farmall H, '50 Farmall Cub
105 x2 (parts)