Welcome to OCC! I wasn't able to find anything about the 2155 throttle springs, but I'm no expert on those newer tractors. I'm better suited to my narrow frames. However, I'm certain there's someone here who can help you out with this
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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)