Electric Relay experts please help

[locry]

I installed powerseats in my 124 which did not originally come with power seats, i have just recently acquired the powerseat switches. I'm missing all the wiring and the control box. It's very difficult to acquire parts where i live, so i think it would be easier if i just made my own "relay box"

anybody have ideas on how to make one from scratch?

my main concern is how to wire the relays and how many relays do i use? i'm thinking 4 for each motor, 2 would turn the motor one way and the other two would turn the motor the other way. for a total of 20 realys?!?!?!

although the switch by itself is constructed in such a way that when toggled it reverses polarity to the motors, thereby turning the motor both ways. I don't want to have to wire the entire thing through the switches. That's why i need to install relays, but i don't really know how to go about it. The original mercedes control box uses just 10 relays, i'm guessing that's 2 relays per motor, as there are 5 motors. I just can't see how they made it work using just 2 relays per motor. HELP!!!!