Recently acquired a 1987 300TD with a transplanted engine. The transplant (combined with my lack of knowledge) is creating confusion on a couple of issues.

On the side of the head, there are five core holes. In one of them, there SHOULD be 005-542-26-17, the temp sender to the gauge. But it's not there. In its place, is a green, 3-pole part that I haven't been able to identify yet. There is a dangling lead which is DEFINITELY the lead to the temp gauge...but there's nothing it could connect to (it could reach hole #1 [currently unused] or hole #2 [occupied by the the green, 3-pole part]).

Is the solution simply to install the correct sender in hole #1?

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 160k miles
06 E320 CDI "Rutherford", Black on Tan, 180k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 79k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife