First of all I think you have the wrong PG TPS sensor , I might be wrong , but all you need is 3 pin one . If a 4 pin is what’s arrived on the throttle bodies then that’s what we will run with then , but I would still double check it is correct or not.
With regards to pin 43 , 71 , 87 , those pins will need to end up at the new tps ok. Those wires all go through the multi plug in the engine fuse box area as they then end up at the throttle pedal . Thats why your not getting a connection from the 6 pin in the picture of the Motorised throttle body plug to those pins . You need to avert you attention to the throttle pedal. That where the wires end up
So if it was me , I would intercept the wires at the white multi plug and de-pin them and label what they are .
One will be 5v power that’s easy to find as it’ll be coming from the ecu and that’s PIN 71
Another one will be the earth for the TPS and that’s PIN 87 , and the Signal wire for the TPS is PIN 43.
If you need any more help just message me .