5v Circuit design help for remote receiver.

[fishgoh0nk[TK]]

I've been trying to wire up a remote system for my raspberry pi with a 5v 315mhz receiver, and planning to use the Pi's 3.3V high to close the circuit with an BJT NPN. What's confusing me is the step down from 5v to 3v3 after the momentary switch has been enabled; Pi's input takes 3v3 max as a pull up; I'm not very savvy with resistances; could someone offer me up their help?

 

Voltage outputs: the Pi has a 5v rail pin, max 16mA and a 3v3 pin

Grounds: the Pi has various ground pins

Inputs: the Pi has various pins rated  3v3 to detect signal highs and lows

Components: The momentary receiver board has a 5v in, ground, and 4 outs (D0, D1, D2, D3, each corresponding to what remote button is pressed), I'm assuming these will also be 5v. I want to connect these outs to the 3v3 pin, but I don't want to exceed the 3v3 pin max. 

 

I plan to step down the voltage with a series divider, but I'm not sure if the receiver chip is its own "circuit" or not. The image on the left assumes the 5v in and 5v out are on different phases, the one on the right is a singular circuit but the 5v in has been stepped down to 2.5, which won't fly to run the receiver circuit. Any thoughts would be extremely appreciated!