“Leveling guide” refers to a bucket level indicator, the sliding rod type works for bucket and forks. The rod attaches to a SSQA pin, not the bucket, so it stays on at all times. (Just for clarity it’s the plain silver bent rod above the hydraulic hoses on the inner right boom in the photos.)
Forks will probably be a different point on the rod (mine are) but it’s not difficult to mark two places on the rod or just know how far to offset it for forks.
Of course that style (mine is OEM) only tells you bucket / fork position at ground. Have seen a variety of homegrown designs, some sophisticated enough to show level throughout lift range. If it’s some other design I have no clue about bucket to fork usefulness.
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