hmmmm that's odd.every 20r i've ever seen had all 3 holes.I did a p/s conversion on my 79 and everything bolted right up.Had to change distributor though.All parts came from a 22r.I've got another 20r in the shed that i will look at tom. and see if it's different,it doesnt even have the mounting place for the fuel pump but i never payed any attention to where a p/s pump would mount,that's just got me wanderin.As far as putting the pump on the pass side of motor just remeber the lines are still gonna have to run over the motor to the drivers side.i