I have the Bennett 351 Trim Tabs. The motor, valves and reservoir are mounted on the aft bulkhead between the fuel tanks and over the bilge sump, which seems standard for the 22s and 23s. It is hard to see and to reach, but it appears as if the fill hole is beneath the Lexan cover and is tiny. Is it best to remove the entire unit to fill it, or is there an easier way, maybe with a syringe or something?